[alsa-devel] [PATCH v4 00/12] introduce skip_spaces(), reducing code size plus some clean-ups
This patch reduces lib.a code size by 173 bytes on my Core 2 with gcc 4.4.1 even considering that it exports a newly defined function skip_spaces() to drivers: text data bss dec hex filename 64867 840 592 66299 102fb (TOTALS-lib.a-before) 64954 584 588 66126 1024e (TOTALS-lib.a-after) and implements some code tidy up.
Besides reducing lib.a size, it converts many in-tree drivers to use the newly defined function, which makes another small reduction on kernel size overall when those drivers are used.
p.s.: Ingo, I hope to have finally fixed my environment by using send-email now. Please let me know if you have any problem with these and thank you for the good advice. get_maintainer.pl gave lots of people as output, I hope that's ok.
Changelog: v4: convert drivers over newly defined skip_spaces() function v3: improved comments on patch 5/7 and factorize a switch statement on 6/7 as per suggestions from Ingo and Frederic (thanks!) v2: addressed feedback from Frederic Weisbecker review (thanks!!) and split into separate patches v1: original submission
André Goddard Rosa (12): vsprintf: factorize "(null)" string vsprintf: pre-calculate final string length for later use vsprintf: give it some care to please checkpatch.pl vsprintf: use TOLOWER whenever possible vsprintf: reduce code size by avoiding extra check vsprintf: move local vars to block local vars and remove unneeded ones vsprintf: factor out skip_space code in a separate function vsprintf: reuse almost identical simple_strtoulX() functions ctype: constify read-only _ctype string string: factorize skip_spaces and export it to be generally available string: on strstrip(), first remove leading spaces before running over str tree-wide: convert open calls to remove spaces to skip_spaces() lib function
arch/s390/kernel/debug.c | 3 +- arch/um/drivers/mconsole_kern.c | 16 +- arch/x86/kernel/cpu/mtrr/if.c | 11 +- drivers/md/dm-table.c | 6 +- drivers/md/md.c | 4 +- drivers/parisc/pdc_stable.c | 9 +- drivers/platform/x86/thinkpad_acpi.c | 7 +- drivers/pnp/interface.c | 36 +--- drivers/s390/block/dasd_proc.c | 5 +- drivers/video/backlight/lcd.c | 4 +- drivers/video/display/display-sysfs.c | 2 +- fs/cachefiles/daemon.c | 8 +- fs/ext4/super.c | 7 +- include/linux/ctype.h | 2 +- include/linux/string.h | 1 + kernel/params.c | 8 +- lib/argv_split.c | 13 +- lib/ctype.c | 50 +++--- lib/dynamic_debug.c | 4 +- lib/string.c | 19 ++- lib/vsprintf.c | 342 ++++++++++++++++----------------- net/irda/irnet/irnet.h | 1 + net/irda/irnet/irnet_ppp.c | 8 +- net/netfilter/xt_recent.c | 3 +- sound/pci/hda/hda_hwdep.c | 7 +- 25 files changed, 264 insertions(+), 312 deletions(-)
Change "<NULL>" to "(null)" and make it a static const char[] hoping that the compiler will make null_str a label to a read-only area containing it.
See: http://people.redhat.com/drepper/dsohowto.pdf part 2.4.2 http://udrepper.livejournal.com/13851.html http://udrepper.livejournal.com/15119.html
Signed-off-by: André Goddard Rosa andre.goddard@gmail.com Acked-by: Frederic Weisbecker fweisbec@gmail.com --- lib/vsprintf.c | 10 ++++++---- 1 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 33bed5e..002f462 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -34,6 +34,8 @@ /* Works only for digits and letters, but small and fast */ #define TOLOWER(x) ((x) | 0x20)
+static const char null_str[] = "(null)"; + static unsigned int simple_guess_base(const char *cp) { if (cp[0] == '0') { @@ -546,12 +548,12 @@ static char *number(char *buf, char *end, unsigned long long num, return buf; }
-static char *string(char *buf, char *end, char *s, struct printf_spec spec) +static char *string(char *buf, char *end, const char *s, struct printf_spec spec) { int len, i;
if ((unsigned long)s < PAGE_SIZE) - s = "<NULL>"; + s = null_str;
len = strnlen(s, spec.precision);
@@ -822,7 +824,7 @@ static char *pointer(const char *fmt, char *buf, char *end, void *ptr, struct printf_spec spec) { if (!ptr) - return string(buf, end, "(null)", spec); + return string(buf, end, null_str, spec);
switch (*fmt) { case 'F': @@ -1445,7 +1447,7 @@ do { \ size_t len; if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE || (unsigned long)save_str < PAGE_SIZE) - save_str = "<NULL>"; + save_str = null_str; len = strlen(save_str); if (str + len + 1 < end) memcpy(str, save_str, len + 1);
Signed-off-by: André Goddard Rosa andre.goddard@gmail.com Acked-by: Frederic Weisbecker fweisbec@gmail.com --- lib/vsprintf.c | 10 ++++++---- 1 files changed, 6 insertions(+), 4 deletions(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 002f462..403e835 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1445,13 +1445,15 @@ do { \ case FORMAT_TYPE_STR: { const char *save_str = va_arg(args, char *); size_t len; + if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE || (unsigned long)save_str < PAGE_SIZE) save_str = null_str; - len = strlen(save_str); - if (str + len + 1 < end) - memcpy(str, save_str, len + 1); - str += len + 1; + len = strlen(save_str) + 1; + if (str + len < end) + memcpy(str, save_str, len); + str += len; + break; }
Most relevant complaints were addressed.
Signed-off-by: André Goddard Rosa andre.goddard@gmail.com Acked-by: Frederic Weisbecker fweisbec@gmail.com --- lib/vsprintf.c | 186 ++++++++++++++++++++++++++++++-------------------------- 1 files changed, 99 insertions(+), 87 deletions(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 403e835..00153c5 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -9,7 +9,7 @@ * Wirzenius wrote this portably, Torvalds fucked it up :-) */
-/* +/* * Fri Jul 13 2001 Crutcher Dunnavant crutcher+kernel@datastacks.com * - changed to provide snprintf and vsnprintf functions * So Feb 1 16:51:32 CET 2004 Juergen Quade quade@hsnr.de @@ -73,9 +73,9 @@ unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) result = result * base + value; cp++; } - if (endp) *endp = (char *)cp; + return result; } EXPORT_SYMBOL(simple_strtoul); @@ -88,8 +88,9 @@ EXPORT_SYMBOL(simple_strtoul); */ long simple_strtol(const char *cp, char **endp, unsigned int base) { - if(*cp == '-') + if (*cp == '-') return -simple_strtoul(cp + 1, endp, base); + return simple_strtoul(cp, endp, base); } EXPORT_SYMBOL(simple_strtol); @@ -119,9 +120,9 @@ unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int bas result = result * base + value; cp++; } - if (endp) *endp = (char *)cp; + return result; } EXPORT_SYMBOL(simple_strtoull); @@ -134,8 +135,9 @@ EXPORT_SYMBOL(simple_strtoull); */ long long simple_strtoll(const char *cp, char **endp, unsigned int base) { - if(*cp=='-') + if (*cp == '-') return -simple_strtoull(cp + 1, endp, base); + return simple_strtoull(cp, endp, base); }
@@ -175,6 +177,7 @@ int strict_strtoul(const char *cp, unsigned int base, unsigned long *res) val = simple_strtoul(cp, &tail, base); if (tail == cp) return -EINVAL; + if ((*tail == '\0') || ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) { *res = val; @@ -287,10 +290,11 @@ EXPORT_SYMBOL(strict_strtoll);
static int skip_atoi(const char **s) { - int i=0; + int i = 0;
while (isdigit(**s)) i = i*10 + *((*s)++) - '0'; + return i; }
@@ -304,7 +308,7 @@ static int skip_atoi(const char **s) /* Formats correctly any integer in [0,99999]. * Outputs from one to five digits depending on input. * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */ -static char* put_dec_trunc(char *buf, unsigned q) +static char *put_dec_trunc(char *buf, unsigned q) { unsigned d3, d2, d1, d0; d1 = (q>>4) & 0xf; @@ -333,14 +337,15 @@ static char* put_dec_trunc(char *buf, unsigned q) d3 = d3 - 10*q; *buf++ = d3 + '0'; /* next digit */ if (q != 0) - *buf++ = q + '0'; /* most sign. digit */ + *buf++ = q + '0'; /* most sign. digit */ } } } + return buf; } /* Same with if's removed. Always emits five digits */ -static char* put_dec_full(char *buf, unsigned q) +static char *put_dec_full(char *buf, unsigned q) { /* BTW, if q is in [0,9999], 8-bit ints will be enough, */ /* but anyway, gcc produces better code with full-sized ints */ @@ -349,14 +354,15 @@ static char* put_dec_full(char *buf, unsigned q) d2 = (q>>8) & 0xf; d3 = (q>>12);
- /* Possible ways to approx. divide by 10 */ - /* gcc -O2 replaces multiply with shifts and adds */ - // (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386) - // (x * 0x67) >> 10: 1100111 - // (x * 0x34) >> 9: 110100 - same - // (x * 0x1a) >> 8: 11010 - same - // (x * 0x0d) >> 7: 1101 - same, shortest code (on i386) - + /* + * Possible ways to approx. divide by 10 + * gcc -O2 replaces multiply with shifts and adds + * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386) + * (x * 0x67) >> 10: 1100111 + * (x * 0x34) >> 9: 110100 - same + * (x * 0x1a) >> 8: 11010 - same + * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386) + */ d0 = 6*(d3 + d2 + d1) + (q & 0xf); q = (d0 * 0xcd) >> 11; d0 = d0 - 10*q; @@ -377,10 +383,11 @@ static char* put_dec_full(char *buf, unsigned q) d3 = d3 - 10*q; *buf++ = d3 + '0'; *buf++ = q + '0'; + return buf; } /* No inlining helps gcc to use registers better */ -static noinline char* put_dec(char *buf, unsigned long long num) +static noinline char *put_dec(char *buf, unsigned long long num) { while (1) { unsigned rem; @@ -450,9 +457,9 @@ static char *number(char *buf, char *end, unsigned long long num, spec.flags &= ~ZEROPAD; sign = 0; if (spec.flags & SIGN) { - if ((signed long long) num < 0) { + if ((signed long long)num < 0) { sign = '-'; - num = - (signed long long) num; + num = -(signed long long)num; spec.field_width--; } else if (spec.flags & PLUS) { sign = '+'; @@ -480,7 +487,9 @@ static char *number(char *buf, char *end, unsigned long long num, else if (spec.base != 10) { /* 8 or 16 */ int mask = spec.base - 1; int shift = 3; - if (spec.base == 16) shift = 4; + + if (spec.base == 16) + shift = 4; do { tmp[i++] = (digits[((unsigned char)num) & mask] | locase); num >>= shift; @@ -495,7 +504,7 @@ static char *number(char *buf, char *end, unsigned long long num, /* leading space padding */ spec.field_width -= spec.precision; if (!(spec.flags & (ZEROPAD+LEFT))) { - while(--spec.field_width >= 0) { + while (--spec.field_width >= 0) { if (buf < end) *buf = ' '; ++buf; @@ -545,6 +554,7 @@ static char *number(char *buf, char *end, unsigned long long num, *buf = ' '; ++buf; } + return buf; }
@@ -574,6 +584,7 @@ static char *string(char *buf, char *end, const char *s, struct printf_spec spec *buf = ' '; ++buf; } + return buf; }
@@ -587,11 +598,13 @@ static char *symbol_string(char *buf, char *end, void *ptr, sprint_symbol(sym, value); else kallsyms_lookup(value, NULL, NULL, NULL, sym); + return string(buf, end, sym, spec); #else - spec.field_width = 2*sizeof(void *); + spec.field_width = 2 * sizeof(void *); spec.flags |= SPECIAL | SMALL | ZEROPAD; spec.base = 16; + return number(buf, end, value, spec); #endif } @@ -611,7 +624,7 @@ static char *resource_string(char *buf, char *end, struct resource *res, .precision = -1, .flags = SPECIAL | SMALL | ZEROPAD, }; - /* room for the actual numbers, the two "0x", -, [, ] and the final zero */ + /* room for actual numbers: the two "0x", -, [, ] and the final zero */ char sym[4*sizeof(resource_size_t) + 8]; char *p = sym, *pend = sym + sizeof(sym); int size = -1; @@ -668,22 +681,19 @@ static char *ip4_string(char *p, const u8 *addr, bool leading_zeros) if (i < 3) *p++ = '.'; } - *p = '\0'; + return p; }
static char *ip6_compressed_string(char *p, const char *addr) { - int i; - int j; - int range; + int i, j, range; unsigned char zerolength[8]; int longest = 1; int colonpos = -1; u16 word; - u8 hi; - u8 lo; + u8 hi, lo; bool needcolon = false; bool useIPv4; struct in6_addr in6; @@ -750,22 +760,23 @@ static char *ip6_compressed_string(char *p, const char *addr) *p++ = ':'; p = ip4_string(p, &in6.s6_addr[12], false); } - *p = '\0'; + return p; }
static char *ip6_string(char *p, const char *addr, const char *fmt) { int i; + for (i = 0; i < 8; i++) { p = pack_hex_byte(p, *addr++); p = pack_hex_byte(p, *addr++); if (fmt[0] == 'I' && i != 7) *p++ = ':'; } - *p = '\0'; + return p; }
@@ -1271,7 +1282,8 @@ int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) { int i;
- i=vsnprintf(buf,size,fmt,args); + i = vsnprintf(buf, size, fmt, args); + return (i >= size) ? (size - 1) : i; } EXPORT_SYMBOL(vscnprintf); @@ -1290,14 +1302,15 @@ EXPORT_SYMBOL(vscnprintf); * * See the vsnprintf() documentation for format string extensions over C99. */ -int snprintf(char * buf, size_t size, const char *fmt, ...) +int snprintf(char *buf, size_t size, const char *fmt, ...) { va_list args; int i;
va_start(args, fmt); - i=vsnprintf(buf,size,fmt,args); + i = vsnprintf(buf, size, fmt, args); va_end(args); + return i; } EXPORT_SYMBOL(snprintf); @@ -1313,7 +1326,7 @@ EXPORT_SYMBOL(snprintf); * the trailing '\0'. If @size is <= 0 the function returns 0. */
-int scnprintf(char * buf, size_t size, const char *fmt, ...) +int scnprintf(char *buf, size_t size, const char *fmt, ...) { va_list args; int i; @@ -1321,6 +1334,7 @@ int scnprintf(char * buf, size_t size, const char *fmt, ...) va_start(args, fmt); i = vsnprintf(buf, size, fmt, args); va_end(args); + return (i >= size) ? (size - 1) : i; } EXPORT_SYMBOL(scnprintf); @@ -1358,14 +1372,15 @@ EXPORT_SYMBOL(vsprintf); * * See the vsnprintf() documentation for format string extensions over C99. */ -int sprintf(char * buf, const char *fmt, ...) +int sprintf(char *buf, const char *fmt, ...) { va_list args; int i;
va_start(args, fmt); - i=vsnprintf(buf, INT_MAX, fmt, args); + i = vsnprintf(buf, INT_MAX, fmt, args); va_end(args); + return i; } EXPORT_SYMBOL(sprintf); @@ -1423,7 +1438,6 @@ do { \ str += sizeof(type); \ } while (0)
- while (*fmt) { read = format_decode(fmt, &spec);
@@ -1512,8 +1526,8 @@ do { \ } } } - return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
+ return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; #undef save_arg } EXPORT_SYMBOL_GPL(vbin_printf); @@ -1545,7 +1559,6 @@ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) unsigned long long num; char *str, *end, c; const char *args = (const char *)bin_buf; - struct printf_spec spec = {0};
if (WARN_ON_ONCE((int) size < 0)) @@ -1725,6 +1738,7 @@ int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) va_start(args, fmt); ret = vbin_printf(bin_buf, size, fmt, args); va_end(args); + return ret; } EXPORT_SYMBOL_GPL(bprintf); @@ -1737,18 +1751,16 @@ EXPORT_SYMBOL_GPL(bprintf); * @fmt: format of buffer * @args: arguments */ -int vsscanf(const char * buf, const char * fmt, va_list args) +int vsscanf(const char *buf, const char *fmt, va_list args) { const char *str = buf; char *next; char digit; int num = 0; - int qualifier; - int base; - int field_width; + int qualifier, base, field_width; int is_sign = 0;
- while(*fmt && *str) { + while (*fmt && *str) { /* skip any white space in format */ /* white space in format matchs any amount of * white space, including none, in the input. @@ -1770,7 +1782,7 @@ int vsscanf(const char * buf, const char * fmt, va_list args) if (!*fmt) break; ++fmt; - + /* skip this conversion. * advance both strings to next white space */ @@ -1808,10 +1820,10 @@ int vsscanf(const char * buf, const char * fmt, va_list args) if (!*fmt || !*str) break;
- switch(*fmt++) { + switch (*fmt++) { case 'c': { - char *s = (char *) va_arg(args,char*); + char *s = (char *)va_arg(args, char*); if (field_width == -1) field_width = 1; do { @@ -1822,17 +1834,16 @@ int vsscanf(const char * buf, const char * fmt, va_list args) continue; case 's': { - char *s = (char *) va_arg(args, char *); - if(field_width == -1) + char *s = (char *)va_arg(args, char *); + if (field_width == -1) field_width = INT_MAX; /* first, skip leading white space in buffer */ while (isspace(*str)) str++;
/* now copy until next white space */ - while (*str && !isspace(*str) && field_width--) { + while (*str && !isspace(*str) && field_width--) *s++ = *str++; - } *s = '\0'; num++; } @@ -1840,7 +1851,7 @@ int vsscanf(const char * buf, const char * fmt, va_list args) case 'n': /* return number of characters read so far */ { - int *i = (int *)va_arg(args,int*); + int *i = (int *)va_arg(args, int*); *i = str - buf; } continue; @@ -1852,14 +1863,14 @@ int vsscanf(const char * buf, const char * fmt, va_list args) base = 16; break; case 'i': - base = 0; + base = 0; case 'd': is_sign = 1; case 'u': break; case '%': /* looking for '%' in str */ - if (*str++ != '%') + if (*str++ != '%') return num; continue; default: @@ -1878,63 +1889,63 @@ int vsscanf(const char * buf, const char * fmt, va_list args) digit = *(str + 1);
if (!digit - || (base == 16 && !isxdigit(digit)) - || (base == 10 && !isdigit(digit)) - || (base == 8 && (!isdigit(digit) || digit > '7')) - || (base == 0 && !isdigit(digit))) - break; + || (base == 16 && !isxdigit(digit)) + || (base == 10 && !isdigit(digit)) + || (base == 8 && (!isdigit(digit) || digit > '7')) + || (base == 0 && !isdigit(digit))) + break;
- switch(qualifier) { + switch (qualifier) { case 'H': /* that's 'hh' in format */ if (is_sign) { - signed char *s = (signed char *) va_arg(args,signed char *); - *s = (signed char) simple_strtol(str,&next,base); + signed char *s = (signed char *)va_arg(args, signed char *); + *s = (signed char)simple_strtol(str, &next, base); } else { - unsigned char *s = (unsigned char *) va_arg(args, unsigned char *); - *s = (unsigned char) simple_strtoul(str, &next, base); + unsigned char *s = (unsigned char *)va_arg(args, unsigned char *); + *s = (unsigned char)simple_strtoul(str, &next, base); } break; case 'h': if (is_sign) { - short *s = (short *) va_arg(args,short *); - *s = (short) simple_strtol(str,&next,base); + short *s = (short *)va_arg(args, short *); + *s = (short)simple_strtol(str, &next, base); } else { - unsigned short *s = (unsigned short *) va_arg(args, unsigned short *); - *s = (unsigned short) simple_strtoul(str, &next, base); + unsigned short *s = (unsigned short *)va_arg(args, unsigned short *); + *s = (unsigned short)simple_strtoul(str, &next, base); } break; case 'l': if (is_sign) { - long *l = (long *) va_arg(args,long *); - *l = simple_strtol(str,&next,base); + long *l = (long *)va_arg(args, long *); + *l = simple_strtol(str, &next, base); } else { - unsigned long *l = (unsigned long*) va_arg(args,unsigned long*); - *l = simple_strtoul(str,&next,base); + unsigned long *l = (unsigned long *)va_arg(args, unsigned long *); + *l = simple_strtoul(str, &next, base); } break; case 'L': if (is_sign) { - long long *l = (long long*) va_arg(args,long long *); - *l = simple_strtoll(str,&next,base); + long long *l = (long long *)va_arg(args, long long *); + *l = simple_strtoll(str, &next, base); } else { - unsigned long long *l = (unsigned long long*) va_arg(args,unsigned long long*); - *l = simple_strtoull(str,&next,base); + unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *); + *l = simple_strtoull(str, &next, base); } break; case 'Z': case 'z': { - size_t *s = (size_t*) va_arg(args,size_t*); - *s = (size_t) simple_strtoul(str,&next,base); + size_t *s = (size_t *)va_arg(args, size_t *); + *s = (size_t)simple_strtoul(str, &next, base); } break; default: if (is_sign) { - int *i = (int *) va_arg(args, int*); - *i = (int) simple_strtol(str,&next,base); + int *i = (int *)va_arg(args, int *); + *i = (int)simple_strtol(str, &next, base); } else { - unsigned int *i = (unsigned int*) va_arg(args, unsigned int*); - *i = (unsigned int) simple_strtoul(str,&next,base); + unsigned int *i = (unsigned int *)va_arg(args, unsigned int*); + *i = (unsigned int)simple_strtoul(str, &next, base); } break; } @@ -1965,14 +1976,15 @@ EXPORT_SYMBOL(vsscanf); * @fmt: formatting of buffer * @...: resulting arguments */ -int sscanf(const char * buf, const char * fmt, ...) +int sscanf(const char *buf, const char *fmt, ...) { va_list args; int i;
- va_start(args,fmt); - i = vsscanf(buf,fmt,args); + va_start(args, fmt); + i = vsscanf(buf, fmt, args); va_end(args); + return i; } EXPORT_SYMBOL(sscanf);
It decreases code size as well: text data bss dec hex filename 15767 0 8 15775 3d9f lib/vsprintf.o-before 15735 0 8 15743 3d7f lib/vsprintf.o-TOLOWER
Signed-off-by: André Goddard Rosa andre.goddard@gmail.com Acked-by: Frederic Weisbecker fweisbec@gmail.com --- lib/vsprintf.c | 15 +++++++-------- 1 files changed, 7 insertions(+), 8 deletions(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 00153c5..14e4197 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -983,8 +983,8 @@ precision: qualifier: /* get the conversion qualifier */ spec->qualifier = -1; - if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || - *fmt == 'Z' || *fmt == 'z' || *fmt == 't') { + if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || + TOLOWER(*fmt) == 'z' || *fmt == 't') { spec->qualifier = *fmt++; if (unlikely(spec->qualifier == *fmt)) { if (spec->qualifier == 'l') { @@ -1051,7 +1051,7 @@ qualifier: spec->type = FORMAT_TYPE_LONG; else spec->type = FORMAT_TYPE_ULONG; - } else if (spec->qualifier == 'Z' || spec->qualifier == 'z') { + } else if (TOLOWER(spec->qualifier) == 'z') { spec->type = FORMAT_TYPE_SIZE_T; } else if (spec->qualifier == 't') { spec->type = FORMAT_TYPE_PTRDIFF; @@ -1198,8 +1198,7 @@ int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) if (qualifier == 'l') { long *ip = va_arg(args, long *); *ip = (str - buf); - } else if (qualifier == 'Z' || - qualifier == 'z') { + } else if (TOLOWER(qualifier) == 'z') { size_t *ip = va_arg(args, size_t *); *ip = (str - buf); } else { @@ -1490,7 +1489,7 @@ do { \ void *skip_arg; if (qualifier == 'l') skip_arg = va_arg(args, long *); - else if (qualifier == 'Z' || qualifier == 'z') + else if (TOLOWER(qualifier) == 'z') skip_arg = va_arg(args, size_t *); else skip_arg = va_arg(args, int *); @@ -1801,8 +1800,8 @@ int vsscanf(const char *buf, const char *fmt, va_list args)
/* get conversion qualifier */ qualifier = -1; - if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' || - *fmt == 'Z' || *fmt == 'z') { + if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || + TOLOWER(*fmt) == 'z') { qualifier = *fmt++; if (unlikely(qualifier == *fmt)) { if (qualifier == 'h') {
No functional change, just refactor the code so that it avoid checking "if (hi)" two times in a sequence, taking advantage of previous check made.
It also reduces code size: text data bss dec hex filename 15735 0 8 15743 3d7f lib/vsprintf.o-before 15719 0 8 15727 3d6f lib/vsprintf.o-minus-double-check
Signed-off-by: André Goddard Rosa andre.goddard@gmail.com Acked-by: Frederic Weisbecker fweisbec@gmail.com --- lib/vsprintf.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 14e4197..af79152 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -747,8 +747,9 @@ static char *ip6_compressed_string(char *p, const char *addr) p = pack_hex_byte(p, hi); else *p++ = hex_asc_lo(hi); + p = pack_hex_byte(p, lo); } - if (hi || lo > 0x0f) + else if (lo > 0x0f) p = pack_hex_byte(p, lo); else *p++ = hex_asc_lo(lo);
Cleanup by moving variables closer to the scope where they're used in fact. Also, remove unneeded ones.
Signed-off-by: André Goddard Rosa andre.goddard@gmail.com Acked-by: Frederic Weisbecker fweisbec@gmail.com --- lib/vsprintf.c | 64 ++++++++++++++++++++++++------------------------------- 1 files changed, 28 insertions(+), 36 deletions(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index af79152..f703fdf 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -842,8 +842,8 @@ static char *pointer(const char *fmt, char *buf, char *end, void *ptr, case 'F': case 'f': ptr = dereference_function_descriptor(ptr); - case 's': /* Fallthrough */ + case 's': case 'S': return symbol_string(buf, end, ptr, spec, *fmt); case 'R': @@ -1105,8 +1105,7 @@ qualifier: int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) { unsigned long long num; - char *str, *end, c; - int read; + char *str, *end; struct printf_spec spec = {0};
/* Reject out-of-range values early. Large positive sizes are @@ -1125,8 +1124,7 @@ int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
while (*fmt) { const char *old_fmt = fmt; - - read = format_decode(fmt, &spec); + int read = format_decode(fmt, &spec);
fmt += read;
@@ -1150,7 +1148,9 @@ int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) spec.precision = va_arg(args, int); break;
- case FORMAT_TYPE_CHAR: + case FORMAT_TYPE_CHAR: { + char c; + if (!(spec.flags & LEFT)) { while (--spec.field_width > 0) { if (str < end) @@ -1169,6 +1169,7 @@ int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) ++str; } break; + }
case FORMAT_TYPE_STR: str = string(str, end, va_arg(args, char *), spec); @@ -1413,7 +1414,6 @@ int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) { struct printf_spec spec = {0}; char *str, *end; - int read;
str = (char *)bin_buf; end = (char *)(bin_buf + size); @@ -1439,12 +1439,14 @@ do { \ } while (0)
while (*fmt) { - read = format_decode(fmt, &spec); + int read = format_decode(fmt, &spec);
fmt += read;
switch (spec.type) { case FORMAT_TYPE_NONE: + case FORMAT_TYPE_INVALID: + case FORMAT_TYPE_PERCENT_CHAR: break;
case FORMAT_TYPE_WIDTH: @@ -1478,12 +1480,6 @@ do { \ fmt++; break;
- case FORMAT_TYPE_PERCENT_CHAR: - break; - - case FORMAT_TYPE_INVALID: - break; - case FORMAT_TYPE_NRCHARS: { /* skip %n 's argument */ int qualifier = spec.qualifier; @@ -1556,10 +1552,9 @@ EXPORT_SYMBOL_GPL(vbin_printf); */ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) { - unsigned long long num; - char *str, *end, c; - const char *args = (const char *)bin_buf; struct printf_spec spec = {0}; + char *str, *end; + const char *args = (const char *)bin_buf;
if (WARN_ON_ONCE((int) size < 0)) return 0; @@ -1589,10 +1584,8 @@ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) }
while (*fmt) { - int read; const char *old_fmt = fmt; - - read = format_decode(fmt, &spec); + int read = format_decode(fmt, &spec);
fmt += read;
@@ -1616,7 +1609,9 @@ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) spec.precision = get_arg(int); break;
- case FORMAT_TYPE_CHAR: + case FORMAT_TYPE_CHAR: { + char c; + if (!(spec.flags & LEFT)) { while (--spec.field_width > 0) { if (str < end) @@ -1634,11 +1629,11 @@ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) ++str; } break; + }
case FORMAT_TYPE_STR: { const char *str_arg = args; - size_t len = strlen(str_arg); - args += len + 1; + args += strlen(str_arg) + 1; str = string(str, end, (char *)str_arg, spec); break; } @@ -1650,11 +1645,6 @@ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) break;
case FORMAT_TYPE_PERCENT_CHAR: - if (str < end) - *str = '%'; - ++str; - break; - case FORMAT_TYPE_INVALID: if (str < end) *str = '%'; @@ -1665,15 +1655,15 @@ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) /* skip */ break;
- default: + default: { + unsigned long long num; + switch (spec.type) {
case FORMAT_TYPE_LONG_LONG: num = get_arg(long long); break; case FORMAT_TYPE_ULONG: - num = get_arg(unsigned long); - break; case FORMAT_TYPE_LONG: num = get_arg(unsigned long); break; @@ -1703,8 +1693,9 @@ int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) }
str = number(str, end, num, spec); - } - } + } /* default: */ + } /* switch(spec.type) */ + } /* while(*fmt) */
if (size > 0) { if (str < end) @@ -1758,7 +1749,7 @@ int vsscanf(const char *buf, const char *fmt, va_list args) char digit; int num = 0; int qualifier, base, field_width; - int is_sign = 0; + bool is_sign;
while (*fmt && *str) { /* skip any white space in format */ @@ -1814,12 +1805,13 @@ int vsscanf(const char *buf, const char *fmt, va_list args) } } } - base = 10; - is_sign = 0;
if (!*fmt || !*str) break;
+ base = 10; + is_sign = 0; + switch (*fmt++) { case 'c': {
It decreases code size: text data bss dec hex filename 15719 0 8 15727 3d6f lib/vsprintf.o-before 15543 0 8 15551 3cbf lib/vsprintf.o-after
Signed-off-by: André Goddard Rosa andre.goddard@gmail.com Acked-by: Frederic Weisbecker fweisbec@gmail.com --- lib/vsprintf.c | 19 +++++++++++-------- 1 files changed, 11 insertions(+), 8 deletions(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index f703fdf..566c947 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1736,6 +1736,13 @@ EXPORT_SYMBOL_GPL(bprintf);
#endif /* CONFIG_BINARY_PRINTF */
+static noinline const char *skip_space(const char *str) +{ + while (isspace(*str)) + ++str; + return str; +} + /** * vsscanf - Unformat a buffer into a list of arguments * @buf: input buffer @@ -1757,10 +1764,8 @@ int vsscanf(const char *buf, const char *fmt, va_list args) * white space, including none, in the input. */ if (isspace(*fmt)) { - while (isspace(*fmt)) - ++fmt; - while (isspace(*str)) - ++str; + fmt = skip_space(fmt); + str = skip_space(str); }
/* anything that is not a conversion must match exactly */ @@ -1830,8 +1835,7 @@ int vsscanf(const char *buf, const char *fmt, va_list args) if (field_width == -1) field_width = INT_MAX; /* first, skip leading white space in buffer */ - while (isspace(*str)) - str++; + str = skip_space(str);
/* now copy until next white space */ while (*str && !isspace(*str) && field_width--) @@ -1873,8 +1877,7 @@ int vsscanf(const char *buf, const char *fmt, va_list args) /* have some sort of integer conversion. * first, skip white space in buffer. */ - while (isspace(*str)) - str++; + str = skip_space(str);
digit = *str; if (is_sign && digit == '-')
The difference between simple_strtoul() and simple_strtoull() is just the size of the variable used to keep track of the sum of characters converted to numbers:
unsigned long simple_strtoul() {...} unsigned long long simple_strtoull(){...}
Both are same size (8 bytes) on my Core 2/gcc 4.4.1. Overflow condition is not checked on both functions, so an extremely large string can break these functions so that they don't even notice it.
As we do not care for overflowing on these functions, always keep the sum using the larger variable around (unsigned long long) on simple_strtoull() and cast it to (unsigned long) on simple_strtoul(), which then becomes just a wrapper around simple_strtoull().
Code size decreases by 304 bytes: text data bss dec hex filename 15543 0 8 15551 3cbf lib/vsprintf.o-before 15239 0 8 15247 3b8f lib/vsprintf.o-after
Signed-off-by: André Goddard Rosa andre.goddard@gmail.com Acked-by: Ingo Molnar mingo@elte.hu --- lib/vsprintf.c | 48 ++++++++++++++---------------------------------- 1 files changed, 14 insertions(+), 34 deletions(-)
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 566c947..7ec96a3 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -49,14 +49,14 @@ static unsigned int simple_guess_base(const char *cp) }
/** - * simple_strtoul - convert a string to an unsigned long + * simple_strtoull - convert a string to an unsigned long long * @cp: The start of the string * @endp: A pointer to the end of the parsed string will be placed here * @base: The number base to use */ -unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) +unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) { - unsigned long result = 0; + unsigned long long result = 0;
if (!base) base = simple_guess_base(cp); @@ -78,54 +78,34 @@ unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
return result; } -EXPORT_SYMBOL(simple_strtoul); +EXPORT_SYMBOL(simple_strtoull);
/** - * simple_strtol - convert a string to a signed long + * simple_strtoul - convert a string to an unsigned long * @cp: The start of the string * @endp: A pointer to the end of the parsed string will be placed here * @base: The number base to use */ -long simple_strtol(const char *cp, char **endp, unsigned int base) +unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) { - if (*cp == '-') - return -simple_strtoul(cp + 1, endp, base); - - return simple_strtoul(cp, endp, base); + return (unsigned long)simple_strtoull(cp, endp, base); } -EXPORT_SYMBOL(simple_strtol); +EXPORT_SYMBOL(simple_strtoul);
/** - * simple_strtoull - convert a string to an unsigned long long + * simple_strtol - convert a string to a signed long * @cp: The start of the string * @endp: A pointer to the end of the parsed string will be placed here * @base: The number base to use */ -unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) +long simple_strtol(const char *cp, char **endp, unsigned int base) { - unsigned long long result = 0; - - if (!base) - base = simple_guess_base(cp); - - if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x') - cp += 2; - - while (isxdigit(*cp)) { - unsigned int value; - - value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10; - if (value >= base) - break; - result = result * base + value; - cp++; - } - if (endp) - *endp = (char *)cp; + if (*cp == '-') + return -simple_strtoul(cp + 1, endp, base);
- return result; + return simple_strtoul(cp, endp, base); } -EXPORT_SYMBOL(simple_strtoull); +EXPORT_SYMBOL(simple_strtol);
/** * simple_strtoll - convert a string to a signed long long
While at it, use tabs to indent the comments.
Signed-off-by: André Goddard Rosa andre.goddard@gmail.com --- include/linux/ctype.h | 2 +- lib/ctype.c | 50 ++++++++++++++++++++++++------------------------ 2 files changed, 26 insertions(+), 26 deletions(-)
diff --git a/include/linux/ctype.h b/include/linux/ctype.h index afa3639..6dec944 100644 --- a/include/linux/ctype.h +++ b/include/linux/ctype.h @@ -15,7 +15,7 @@ #define _X 0x40 /* hex digit */ #define _SP 0x80 /* hard space (0x20) */
-extern unsigned char _ctype[]; +extern const unsigned char _ctype[];
#define __ismask(x) (_ctype[(int)(unsigned char)(x)])
diff --git a/lib/ctype.c b/lib/ctype.c index d02ace1..26baa62 100644 --- a/lib/ctype.c +++ b/lib/ctype.c @@ -7,30 +7,30 @@ #include <linux/ctype.h> #include <linux/module.h>
-unsigned char _ctype[] = { -_C,_C,_C,_C,_C,_C,_C,_C, /* 0-7 */ -_C,_C|_S,_C|_S,_C|_S,_C|_S,_C|_S,_C,_C, /* 8-15 */ -_C,_C,_C,_C,_C,_C,_C,_C, /* 16-23 */ -_C,_C,_C,_C,_C,_C,_C,_C, /* 24-31 */ -_S|_SP,_P,_P,_P,_P,_P,_P,_P, /* 32-39 */ -_P,_P,_P,_P,_P,_P,_P,_P, /* 40-47 */ -_D,_D,_D,_D,_D,_D,_D,_D, /* 48-55 */ -_D,_D,_P,_P,_P,_P,_P,_P, /* 56-63 */ -_P,_U|_X,_U|_X,_U|_X,_U|_X,_U|_X,_U|_X,_U, /* 64-71 */ -_U,_U,_U,_U,_U,_U,_U,_U, /* 72-79 */ -_U,_U,_U,_U,_U,_U,_U,_U, /* 80-87 */ -_U,_U,_U,_P,_P,_P,_P,_P, /* 88-95 */ -_P,_L|_X,_L|_X,_L|_X,_L|_X,_L|_X,_L|_X,_L, /* 96-103 */ -_L,_L,_L,_L,_L,_L,_L,_L, /* 104-111 */ -_L,_L,_L,_L,_L,_L,_L,_L, /* 112-119 */ -_L,_L,_L,_P,_P,_P,_P,_C, /* 120-127 */ -0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 128-143 */ -0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 144-159 */ -_S|_SP,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P, /* 160-175 */ -_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P, /* 176-191 */ -_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U, /* 192-207 */ -_U,_U,_U,_U,_U,_U,_U,_P,_U,_U,_U,_U,_U,_U,_U,_L, /* 208-223 */ -_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L, /* 224-239 */ -_L,_L,_L,_L,_L,_L,_L,_P,_L,_L,_L,_L,_L,_L,_L,_L}; /* 240-255 */ +const unsigned char _ctype[] = { +_C,_C,_C,_C,_C,_C,_C,_C, /* 0-7 */ +_C,_C|_S,_C|_S,_C|_S,_C|_S,_C|_S,_C,_C, /* 8-15 */ +_C,_C,_C,_C,_C,_C,_C,_C, /* 16-23 */ +_C,_C,_C,_C,_C,_C,_C,_C, /* 24-31 */ +_S|_SP,_P,_P,_P,_P,_P,_P,_P, /* 32-39 */ +_P,_P,_P,_P,_P,_P,_P,_P, /* 40-47 */ +_D,_D,_D,_D,_D,_D,_D,_D, /* 48-55 */ +_D,_D,_P,_P,_P,_P,_P,_P, /* 56-63 */ +_P,_U|_X,_U|_X,_U|_X,_U|_X,_U|_X,_U|_X,_U, /* 64-71 */ +_U,_U,_U,_U,_U,_U,_U,_U, /* 72-79 */ +_U,_U,_U,_U,_U,_U,_U,_U, /* 80-87 */ +_U,_U,_U,_P,_P,_P,_P,_P, /* 88-95 */ +_P,_L|_X,_L|_X,_L|_X,_L|_X,_L|_X,_L|_X,_L, /* 96-103 */ +_L,_L,_L,_L,_L,_L,_L,_L, /* 104-111 */ +_L,_L,_L,_L,_L,_L,_L,_L, /* 112-119 */ +_L,_L,_L,_P,_P,_P,_P,_C, /* 120-127 */ +0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 128-143 */ +0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0, /* 144-159 */ +_S|_SP,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P, /* 160-175 */ +_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P,_P, /* 176-191 */ +_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U,_U, /* 192-207 */ +_U,_U,_U,_U,_U,_U,_U,_P,_U,_U,_U,_U,_U,_U,_U,_L, /* 208-223 */ +_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L,_L, /* 224-239 */ +_L,_L,_L,_L,_L,_L,_L,_P,_L,_L,_L,_L,_L,_L,_L,_L}; /* 240-255 */
EXPORT_SYMBOL(_ctype);
On the following sentence: while (*s && isspace(*s)) s++;
If *s == 0, isspace() evaluates to ((_ctype[*s] & 0x20) != 0), which evaluates to ((0x08 & 0x20) != 0) which equals to 0 as well. If *s == 1, we depend on isspace() result anyway.
In other words, "a char equals zero is never a space". So remove this check. Also, *s != 0 is by far the most common case (non-empty string).
Signed-off-by: André Goddard Rosa andre.goddard@gmail.com --- include/linux/string.h | 1 + lib/string.c | 19 +++++++++++++++---- 2 files changed, 16 insertions(+), 4 deletions(-)
diff --git a/include/linux/string.h b/include/linux/string.h index b850886..3bba9ee 100644 --- a/include/linux/string.h +++ b/include/linux/string.h @@ -62,6 +62,7 @@ extern char * strnchr(const char *, size_t, int); #ifndef __HAVE_ARCH_STRRCHR extern char * strrchr(const char *,int); #endif +extern const char * __must_check skip_spaces(const char *); extern char * __must_check strstrip(char *); #ifndef __HAVE_ARCH_STRSTR extern char * strstr(const char *,const char *); diff --git a/lib/string.c b/lib/string.c index b19b87a..d9a51d5 100644 --- a/lib/string.c +++ b/lib/string.c @@ -330,6 +330,20 @@ EXPORT_SYMBOL(strnchr); #endif
/** + * skip_spaces - Removes leading whitespace from @s. + * @s: The string to be stripped. + * + * Returns a pointer to the first non-whitespace character in @s. + */ +const char *skip_spaces(const char *str) +{ + while (isspace(*str)) + ++str; + return str; +} +EXPORT_SYMBOL(skip_spaces); + +/** * strstrip - Removes leading and trailing whitespace from @s. * @s: The string to be stripped. * @@ -352,10 +366,7 @@ char *strstrip(char *s) end--; *(end + 1) = '\0';
- while (*s && isspace(*s)) - s++; - - return s; + return (char *)skip_spaces(s); } EXPORT_SYMBOL(strstrip);
On Sat, 7 Nov 2009 13:16:18 -0200 André Goddard Rosa andre.goddard@gmail.com wrote:
On the following sentence: while (*s && isspace(*s)) s++;
Looks fine but for one thing: it's actually shorter inline than moved into /lib so at the very least it should be a header inline not a function call.
Second minor comment. Although it never made it into the final ANSI C, the proposed name (and the one used in a lot of other non Linux code for this) is stpblk().
Alan
... so that strlen() iterates over a smaller string comprising of the remaining characters only.
Signed-off-by: André Goddard Rosa andre.goddard@gmail.com --- lib/string.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/lib/string.c b/lib/string.c index d9a51d5..cf86eab 100644 --- a/lib/string.c +++ b/lib/string.c @@ -356,8 +356,8 @@ char *strstrip(char *s) size_t size; char *end;
+ s = (char *)skip_spaces(s); size = strlen(s); - if (!size) return s;
@@ -366,7 +366,7 @@ char *strstrip(char *s) end--; *(end + 1) = '\0';
- return (char *)skip_spaces(s); + return s; } EXPORT_SYMBOL(strstrip);
Makes use of skip_spaces() defined in lib/string.c for removing leading spaces from strings all over the tree.
Also, while at it, if we see (*str && isspace(*str)), we can be sure to remove the first condition (*str) as the second one (isspace(*str)) also evaluates to 0 whenever *str == 0, making it redundant. In other words, "a char equals zero is never a space".
Signed-off-by: André Goddard Rosa andre.goddard@gmail.com --- arch/s390/kernel/debug.c | 3 +- arch/um/drivers/mconsole_kern.c | 16 ++++++-------- arch/x86/kernel/cpu/mtrr/if.c | 11 +++------ drivers/md/dm-table.c | 6 +--- drivers/md/md.c | 4 +- drivers/parisc/pdc_stable.c | 9 ++----- drivers/platform/x86/thinkpad_acpi.c | 7 +---- drivers/pnp/interface.c | 36 +++++++++----------------------- drivers/s390/block/dasd_proc.c | 5 ++- drivers/video/backlight/lcd.c | 4 +- drivers/video/display/display-sysfs.c | 2 +- fs/cachefiles/daemon.c | 8 ++---- fs/ext4/super.c | 7 +---- kernel/params.c | 8 ++---- lib/argv_split.c | 13 ++--------- lib/dynamic_debug.c | 4 +- lib/vsprintf.c | 15 +++---------- net/irda/irnet/irnet.h | 1 + net/irda/irnet/irnet_ppp.c | 8 ++---- net/netfilter/xt_recent.c | 3 +- sound/pci/hda/hda_hwdep.c | 7 ++--- 21 files changed, 63 insertions(+), 114 deletions(-)
diff --git a/arch/s390/kernel/debug.c b/arch/s390/kernel/debug.c index 20f282c..7a0f4a9 100644 --- a/arch/s390/kernel/debug.c +++ b/arch/s390/kernel/debug.c @@ -18,6 +18,7 @@ #include <linux/errno.h> #include <linux/slab.h> #include <linux/ctype.h> +#include <linux/string.h> #include <linux/sysctl.h> #include <asm/uaccess.h> #include <linux/module.h> @@ -1183,7 +1184,7 @@ debug_get_uint(char *buf) { int rc;
- for(; isspace(*buf); buf++); + buf = skip_spaces(buf); rc = simple_strtoul(buf, &buf, 10); if(*buf){ rc = -EINVAL; diff --git a/arch/um/drivers/mconsole_kern.c b/arch/um/drivers/mconsole_kern.c index e14629c..f5d459a 100644 --- a/arch/um/drivers/mconsole_kern.c +++ b/arch/um/drivers/mconsole_kern.c @@ -6,6 +6,7 @@
#include <linux/console.h> #include <linux/ctype.h> +#include <linux/string.h> #include <linux/interrupt.h> #include <linux/list.h> #include <linux/mm.h> @@ -131,7 +132,7 @@ void mconsole_proc(struct mc_request *req) char *ptr = req->request.data, *buf;
ptr += strlen("proc"); - while (isspace(*ptr)) ptr++; + ptr = skip_spaces(ptr);
proc = get_fs_type("proc"); if (proc == NULL) { @@ -212,8 +213,7 @@ void mconsole_proc(struct mc_request *req) char *ptr = req->request.data;
ptr += strlen("proc"); - while (isspace(*ptr)) - ptr++; + ptr = skip_spaces(ptr); snprintf(path, sizeof(path), "/proc/%s", ptr);
fd = sys_open(path, 0, 0); @@ -560,8 +560,7 @@ void mconsole_config(struct mc_request *req) int err;
ptr += strlen("config"); - while (isspace(*ptr)) - ptr++; + ptr = skip_spaces(ptr); dev = mconsole_find_dev(ptr); if (dev == NULL) { mconsole_reply(req, "Bad configuration option", 1, 0); @@ -588,7 +587,7 @@ void mconsole_remove(struct mc_request *req) int err, start, end, n;
ptr += strlen("remove"); - while (isspace(*ptr)) ptr++; + ptr = skip_spaces(ptr); dev = mconsole_find_dev(ptr); if (dev == NULL) { mconsole_reply(req, "Bad remove option", 1, 0); @@ -712,7 +711,7 @@ void mconsole_sysrq(struct mc_request *req) char *ptr = req->request.data;
ptr += strlen("sysrq"); - while (isspace(*ptr)) ptr++; + ptr = skip_spaces(ptr);
/* * With 'b', the system will shut down without a chance to reply, @@ -757,8 +756,7 @@ void mconsole_stack(struct mc_request *req) */
ptr += strlen("stack"); - while (isspace(*ptr)) - ptr++; + ptr = skip_spaces(ptr);
/* * Should really check for multiple pids or reject bad args here diff --git a/arch/x86/kernel/cpu/mtrr/if.c b/arch/x86/kernel/cpu/mtrr/if.c index 3c1b12d..e006e56 100644 --- a/arch/x86/kernel/cpu/mtrr/if.c +++ b/arch/x86/kernel/cpu/mtrr/if.c @@ -4,6 +4,7 @@ #include <linux/proc_fs.h> #include <linux/module.h> #include <linux/ctype.h> +#include <linux/string.h> #include <linux/init.h>
#define LINE_SIZE 80 @@ -133,8 +134,7 @@ mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos) return -EINVAL;
base = simple_strtoull(line + 5, &ptr, 0); - while (isspace(*ptr)) - ptr++; + ptr = skip_spaces(ptr);
if (strncmp(ptr, "size=", 5)) return -EINVAL; @@ -142,14 +142,11 @@ mtrr_write(struct file *file, const char __user *buf, size_t len, loff_t * ppos) size = simple_strtoull(ptr + 5, &ptr, 0); if ((base & 0xfff) || (size & 0xfff)) return -EINVAL; - while (isspace(*ptr)) - ptr++; + ptr = skip_spaces(ptr);
if (strncmp(ptr, "type=", 5)) return -EINVAL; - ptr += 5; - while (isspace(*ptr)) - ptr++; + ptr = skip_spaces(ptr + 5);
for (i = 0; i < MTRR_NUM_TYPES; ++i) { if (strcmp(ptr, mtrr_strings[i])) diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c index 1a6cb3c..91976e8 100644 --- a/drivers/md/dm-table.c +++ b/drivers/md/dm-table.c @@ -12,6 +12,7 @@ #include <linux/blkdev.h> #include <linux/namei.h> #include <linux/ctype.h> +#include <linux/string.h> #include <linux/slab.h> #include <linux/interrupt.h> #include <linux/mutex.h> @@ -600,11 +601,8 @@ int dm_split_args(int *argc, char ***argvp, char *input) return -ENOMEM;
while (1) { - start = end; - /* Skip whitespace */ - while (*start && isspace(*start)) - start++; + start = skip_spaces(end);
if (!*start) break; /* success, we hit the end */ diff --git a/drivers/md/md.c b/drivers/md/md.c index 26ba42a..1dcb83c 100644 --- a/drivers/md/md.c +++ b/drivers/md/md.c @@ -39,6 +39,7 @@ #include <linux/buffer_head.h> /* for invalidate_bdev */ #include <linux/poll.h> #include <linux/ctype.h> +#include <linux/string.h> #include <linux/hdreg.h> #include <linux/proc_fs.h> #include <linux/random.h> @@ -3225,8 +3226,7 @@ bitmap_store(mddev_t *mddev, const char *buf, size_t len) } if (*end && !isspace(*end)) break; bitmap_dirty_bits(mddev->bitmap, chunk, end_chunk); - buf = end; - while (isspace(*buf)) buf++; + buf = skip_spaces(end); } bitmap_unplug(mddev->bitmap); /* flush the bits to disk */ out: diff --git a/drivers/parisc/pdc_stable.c b/drivers/parisc/pdc_stable.c index 13a64bc..0bc5d47 100644 --- a/drivers/parisc/pdc_stable.c +++ b/drivers/parisc/pdc_stable.c @@ -779,12 +779,9 @@ static ssize_t pdcs_auto_write(struct kobject *kobj, read_unlock(&pathentry->rw_lock); DPRINTK("%s: flags before: 0x%X\n", __func__, flags); - - temp = in; - - while (*temp && isspace(*temp)) - temp++; - + + temp = skip_spaces(in); + c = *temp++ - '0'; if ((c != 0) && (c != 1)) goto parse_error; diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c index 7e7da18..29dd2dd 100644 --- a/drivers/platform/x86/thinkpad_acpi.c +++ b/drivers/platform/x86/thinkpad_acpi.c @@ -1006,11 +1006,8 @@ static int parse_strtoul(const char *buf, { char *endp;
- while (*buf && isspace(*buf)) - buf++; - *value = simple_strtoul(buf, &endp, 0); - while (*endp && isspace(*endp)) - endp++; + *value = simple_strtoul(skip_spaces(buf), &endp, 0); + endp = skip_spaces(endp); if (*endp || *value > max) return -EINVAL;
diff --git a/drivers/pnp/interface.c b/drivers/pnp/interface.c index c3f1c8e..68b0c04 100644 --- a/drivers/pnp/interface.c +++ b/drivers/pnp/interface.c @@ -310,8 +310,7 @@ static ssize_t pnp_set_current_resources(struct device *dmdev, goto done; }
- while (isspace(*buf)) - ++buf; + buf = skip_spaces(buf); if (!strnicmp(buf, "disable", 7)) { retval = pnp_disable_dev(dev); goto done; @@ -353,19 +352,13 @@ static ssize_t pnp_set_current_resources(struct device *dmdev, pnp_init_resources(dev); mutex_lock(&pnp_res_mutex); while (1) { - while (isspace(*buf)) - ++buf; + buf = skip_spaces(buf); if (!strnicmp(buf, "io", 2)) { - buf += 2; - while (isspace(*buf)) - ++buf; + buf = skip_spaces(buf + 2); start = simple_strtoul(buf, &buf, 0); - while (isspace(*buf)) - ++buf; + buf = skip_spaces(buf); if (*buf == '-') { - buf += 1; - while (isspace(*buf)) - ++buf; + buf = skip_spaces(buf + 1); end = simple_strtoul(buf, &buf, 0); } else end = start; @@ -373,16 +366,11 @@ static ssize_t pnp_set_current_resources(struct device *dmdev, continue; } if (!strnicmp(buf, "mem", 3)) { - buf += 3; - while (isspace(*buf)) - ++buf; + buf = skip_spaces(buf + 3); start = simple_strtoul(buf, &buf, 0); - while (isspace(*buf)) - ++buf; + buf = skip_spaces(buf); if (*buf == '-') { - buf += 1; - while (isspace(*buf)) - ++buf; + buf = skip_spaces(buf + 1); end = simple_strtoul(buf, &buf, 0); } else end = start; @@ -390,17 +378,13 @@ static ssize_t pnp_set_current_resources(struct device *dmdev, continue; } if (!strnicmp(buf, "irq", 3)) { - buf += 3; - while (isspace(*buf)) - ++buf; + buf = skip_spaces(buf + 3); start = simple_strtoul(buf, &buf, 0); pnp_add_irq_resource(dev, start, 0); continue; } if (!strnicmp(buf, "dma", 3)) { - buf += 3; - while (isspace(*buf)) - ++buf; + buf = skip_spaces(buf + 3); start = simple_strtoul(buf, &buf, 0); pnp_add_dma_resource(dev, start, 0); continue; diff --git a/drivers/s390/block/dasd_proc.c b/drivers/s390/block/dasd_proc.c index 654daa3..c2d8792 100644 --- a/drivers/s390/block/dasd_proc.c +++ b/drivers/s390/block/dasd_proc.c @@ -14,6 +14,7 @@ #define KMSG_COMPONENT "dasd"
#include <linux/ctype.h> +#include <linux/string.h> #include <linux/seq_file.h> #include <linux/vmalloc.h> #include <linux/proc_fs.h> @@ -272,10 +273,10 @@ dasd_statistics_write(struct file *file, const char __user *user_buf, DBF_EVENT(DBF_DEBUG, "/proc/dasd/statictics: '%s'\n", buffer);
/* check for valid verbs */ - for (str = buffer; isspace(*str); str++); + str = skip_spaces(buffer); if (strncmp(str, "set", 3) == 0 && isspace(str[3])) { /* 'set xxx' was given */ - for (str = str + 4; isspace(*str); str++); + str = skip_spaces(str + 4); if (strcmp(str, "on") == 0) { /* switch on statistics profiling */ dasd_profile_level = DASD_PROFILE_ON; diff --git a/drivers/video/backlight/lcd.c b/drivers/video/backlight/lcd.c index b644947..3b20cbf 100644 --- a/drivers/video/backlight/lcd.c +++ b/drivers/video/backlight/lcd.c @@ -101,7 +101,7 @@ static ssize_t lcd_store_power(struct device *dev, int power = simple_strtoul(buf, &endp, 0); size_t size = endp - buf;
- if (*endp && isspace(*endp)) + if (isspace(*endp)) size++; if (size != count) return -EINVAL; @@ -140,7 +140,7 @@ static ssize_t lcd_store_contrast(struct device *dev, int contrast = simple_strtoul(buf, &endp, 0); size_t size = endp - buf;
- if (*endp && isspace(*endp)) + if (isspace(*endp)) size++; if (size != count) return -EINVAL; diff --git a/drivers/video/display/display-sysfs.c b/drivers/video/display/display-sysfs.c index 4830b1b..80abbf3 100644 --- a/drivers/video/display/display-sysfs.c +++ b/drivers/video/display/display-sysfs.c @@ -67,7 +67,7 @@ static ssize_t display_store_contrast(struct device *dev, contrast = simple_strtoul(buf, &endp, 0); size = endp - buf;
- if (*endp && isspace(*endp)) + if (isspace(*endp)) size++;
if (size != count) diff --git a/fs/cachefiles/daemon.c b/fs/cachefiles/daemon.c index 4618516..af6d9a6 100644 --- a/fs/cachefiles/daemon.c +++ b/fs/cachefiles/daemon.c @@ -21,6 +21,7 @@ #include <linux/mount.h> #include <linux/statfs.h> #include <linux/ctype.h> +#include <linux/string.h> #include <linux/fs_struct.h> #include "internal.h"
@@ -250,15 +251,12 @@ static ssize_t cachefiles_daemon_write(struct file *file, /* parse the command */ ret = -EOPNOTSUPP;
- for (args = data; *args; args++) - if (isspace(*args)) - break; + args = skip_spaces(data); if (*args) { if (args == data) goto error; *args = '\0'; - for (args++; isspace(*args); args++) - continue; + args = skip_spaces(++args); }
/* run the appropriate command handler */ diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 312211e..580766a 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -2097,11 +2097,8 @@ static int parse_strtoul(const char *buf, { char *endp;
- while (*buf && isspace(*buf)) - buf++; - *value = simple_strtoul(buf, &endp, 0); - while (*endp && isspace(*endp)) - endp++; + *value = simple_strtoul(skip_spaces(buf), &endp, 0); + endp = skip_spaces(endp); if (*endp || *value > max) return -EINVAL;
diff --git a/kernel/params.c b/kernel/params.c index d656c27..cf1b691 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -24,6 +24,7 @@ #include <linux/err.h> #include <linux/slab.h> #include <linux/ctype.h> +#include <linux/string.h>
#if 0 #define DEBUGP printk @@ -122,9 +123,7 @@ static char *next_arg(char *args, char **param, char **val) next = args + i;
/* Chew up trailing spaces. */ - while (isspace(*next)) - next++; - return next; + return skip_spaces(next); }
/* Args looks like "foo=bar,bar2 baz=fuz wiz". */ @@ -139,8 +138,7 @@ int parse_args(const char *name, DEBUGP("Parsing ARGS: %s\n", args);
/* Chew leading spaces */ - while (isspace(*args)) - args++; + args = skip_spaces(args);
while (*args) { int ret; diff --git a/lib/argv_split.c b/lib/argv_split.c index 5205a8d..4b1b083 100644 --- a/lib/argv_split.c +++ b/lib/argv_split.c @@ -4,17 +4,10 @@
#include <linux/kernel.h> #include <linux/ctype.h> +#include <linux/string.h> #include <linux/slab.h> #include <linux/module.h>
-static const char *skip_sep(const char *cp) -{ - while (*cp && isspace(*cp)) - cp++; - - return cp; -} - static const char *skip_arg(const char *cp) { while (*cp && !isspace(*cp)) @@ -28,7 +21,7 @@ static int count_argc(const char *str) int count = 0;
while (*str) { - str = skip_sep(str); + str = skip_spaces(str); if (*str) { count++; str = skip_arg(str); @@ -82,7 +75,7 @@ char **argv_split(gfp_t gfp, const char *str, int *argcp) argvp = argv;
while (*str) { - str = skip_sep(str); + str = skip_spaces(str);
if (*str) { const char *p = str; diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c index e22c148..f935029 100644 --- a/lib/dynamic_debug.c +++ b/lib/dynamic_debug.c @@ -21,6 +21,7 @@ #include <linux/list.h> #include <linux/sysctl.h> #include <linux/ctype.h> +#include <linux/string.h> #include <linux/uaccess.h> #include <linux/dynamic_debug.h> #include <linux/debugfs.h> @@ -209,8 +210,7 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords) char *end;
/* Skip leading whitespace */ - while (*buf && isspace(*buf)) - buf++; + buf = skip_spaces(buf); if (!*buf) break; /* oh, it was trailing whitespace */
diff --git a/lib/vsprintf.c b/lib/vsprintf.c index 7ec96a3..06e0311 100644 --- a/lib/vsprintf.c +++ b/lib/vsprintf.c @@ -1716,13 +1716,6 @@ EXPORT_SYMBOL_GPL(bprintf);
#endif /* CONFIG_BINARY_PRINTF */
-static noinline const char *skip_space(const char *str) -{ - while (isspace(*str)) - ++str; - return str; -} - /** * vsscanf - Unformat a buffer into a list of arguments * @buf: input buffer @@ -1744,8 +1737,8 @@ int vsscanf(const char *buf, const char *fmt, va_list args) * white space, including none, in the input. */ if (isspace(*fmt)) { - fmt = skip_space(fmt); - str = skip_space(str); + fmt = skip_spaces(++fmt); + str = skip_spaces(str); }
/* anything that is not a conversion must match exactly */ @@ -1815,7 +1808,7 @@ int vsscanf(const char *buf, const char *fmt, va_list args) if (field_width == -1) field_width = INT_MAX; /* first, skip leading white space in buffer */ - str = skip_space(str); + str = skip_spaces(str);
/* now copy until next white space */ while (*str && !isspace(*str) && field_width--) @@ -1857,7 +1850,7 @@ int vsscanf(const char *buf, const char *fmt, va_list args) /* have some sort of integer conversion. * first, skip white space in buffer. */ - str = skip_space(str); + str = skip_spaces(str);
digit = *str; if (is_sign && digit == '-') diff --git a/net/irda/irnet/irnet.h b/net/irda/irnet/irnet.h index b001c36..4300df3 100644 --- a/net/irda/irnet/irnet.h +++ b/net/irda/irnet/irnet.h @@ -249,6 +249,7 @@ #include <linux/poll.h> #include <linux/capability.h> #include <linux/ctype.h> /* isspace() */ +#include <linux/string.h> /* skip_spaces() */ #include <asm/uaccess.h> #include <linux/init.h>
diff --git a/net/irda/irnet/irnet_ppp.c b/net/irda/irnet/irnet_ppp.c index 7dea882..156020d 100644 --- a/net/irda/irnet/irnet_ppp.c +++ b/net/irda/irnet/irnet_ppp.c @@ -76,9 +76,8 @@ irnet_ctrl_write(irnet_socket * ap, /* Look at the next command */ start = next;
- /* Scrap whitespaces before the command */ - while(isspace(*start)) - start++; + /* Scrap whitespaces before the command */ + start = skip_spaces(start);
/* ',' is our command separator */ next = strchr(start, ','); @@ -133,8 +132,7 @@ irnet_ctrl_write(irnet_socket * ap, char * endp;
/* Scrap whitespaces before the command */ - while(isspace(*begp)) - begp++; + begp = skip_spaces(begp);
/* Convert argument to a number (last arg is the base) */ addr = simple_strtoul(begp, &endp, 16); diff --git a/net/netfilter/xt_recent.c b/net/netfilter/xt_recent.c index eb0ceb8..fc70a49 100644 --- a/net/netfilter/xt_recent.c +++ b/net/netfilter/xt_recent.c @@ -482,8 +482,7 @@ static ssize_t recent_old_proc_write(struct file *file, if (copy_from_user(buf, input, size)) return -EFAULT;
- while (isspace(*c)) - c++; + c = skip_spaces(c);
if (size - (c - buf) < 5) return c - buf; diff --git a/sound/pci/hda/hda_hwdep.c b/sound/pci/hda/hda_hwdep.c index cc24e67..4e17b43 100644 --- a/sound/pci/hda/hda_hwdep.c +++ b/sound/pci/hda/hda_hwdep.c @@ -24,6 +24,7 @@ #include <linux/compat.h> #include <linux/mutex.h> #include <linux/ctype.h> +#include <linux/string.h> #include <linux/firmware.h> #include <sound/core.h> #include "hda_codec.h" @@ -390,8 +391,7 @@ static int parse_hints(struct hda_codec *codec, const char *buf) char *key, *val; struct hda_hint *hint;
- while (isspace(*buf)) - buf++; + buf = skip_spaces(buf); if (!*buf || *buf == '#' || *buf == '\n') return 0; if (*buf == '=') @@ -406,8 +406,7 @@ static int parse_hints(struct hda_codec *codec, const char *buf) return -EINVAL; } *val++ = 0; - while (isspace(*val)) - val++; + val = skip_spaces(val); remove_trail_spaces(key); remove_trail_spaces(val); hint = get_hint(codec, key);
On Sat, Nov 07, 2009 at 01:16:20PM -0200, André Goddard Rosa wrote:
Makes use of skip_spaces() defined in lib/string.c for removing leading spaces from strings all over the tree.
Also, while at it, if we see (*str && isspace(*str)), we can be sure to remove the first condition (*str) as the second one (isspace(*str)) also evaluates to 0 whenever *str == 0, making it redundant. In other words, "a char equals zero is never a space".
There are a number of places that have the pattern of skipping whitespace, calling simpler_strtoul(), and then skipping whitespace afterwards. And thinkpad_acpi.c and fs/ext4/super.c both have an indentical function, parse_strotul(), which basically does this plus doing actual error checking (a number of callers of simple_strtoul aren't checking to see if the user passed in a valid number or not, boo.)
I would suggest that we should lift parse_strtoul() into lib/, both to save a bit of code, as well as encouraging people to do proper input validation, while we are doing this tree-wide cleanup.
- Ted
Also, while at it, if we see (*str && isspace(*str)), we can be sure to remove the first condition (*str) as the second one (isspace(*str)) also evaluates to 0 whenever *str == 0, making it redundant. In other words, "a char equals zero is never a space".
I tried the following semantic patch (http://coccinelle.lip6.fr), and got the results below.
@@ expression str; @@
( // ignore skip_spaces cases while (*str && isspace(*str)) { (str++;|++str;) } | - *str && isspace(*str) )
I haven't checked the results in any way, however.
julia
diff -u -p a/drivers/leds/led-class.c b/drivers/leds/led-class.c --- a/drivers/leds/led-class.c +++ b/drivers/leds/led-class.c @@ -50,7 +50,7 @@ static ssize_t led_brightness_store(stru unsigned long state = simple_strtoul(buf, &after, 10); size_t count = after - buf;
- if (*after && isspace(*after)) + if (isspace(*after)) count++;
if (count == size) { diff -u -p a/drivers/leds/ledtrig-timer.c b/drivers/leds/ledtrig-timer.c --- a/drivers/leds/ledtrig-timer.c +++ b/drivers/leds/ledtrig-timer.c @@ -83,7 +83,7 @@ static ssize_t led_delay_on_store(struct unsigned long state = simple_strtoul(buf, &after, 10); size_t count = after - buf;
- if (*after && isspace(*after)) + if (isspace(*after)) count++;
if (count == size) { @@ -127,7 +127,7 @@ static ssize_t led_delay_off_store(struc unsigned long state = simple_strtoul(buf, &after, 10); size_t count = after - buf;
- if (*after && isspace(*after)) + if (isspace(*after)) count++;
if (count == size) { diff -u -p a/drivers/video/backlight/lcd.c b/drivers/video/backlight/lcd.c --- a/drivers/video/backlight/lcd.c +++ b/drivers/video/backlight/lcd.c @@ -101,7 +101,7 @@ static ssize_t lcd_store_power(struct de int power = simple_strtoul(buf, &endp, 0); size_t size = endp - buf;
- if (*endp && isspace(*endp)) + if (isspace(*endp)) size++; if (size != count) return -EINVAL; @@ -140,7 +140,7 @@ static ssize_t lcd_store_contrast(struct int contrast = simple_strtoul(buf, &endp, 0); size_t size = endp - buf;
- if (*endp && isspace(*endp)) + if (isspace(*endp)) size++; if (size != count) return -EINVAL; diff -u -p a/drivers/video/display/display-sysfs.c b/drivers/video/display/display-sysfs.c --- a/drivers/video/display/display-sysfs.c +++ b/drivers/video/display/display-sysfs.c @@ -67,7 +67,7 @@ static ssize_t display_store_contrast(st contrast = simple_strtoul(buf, &endp, 0); size = endp - buf;
- if (*endp && isspace(*endp)) + if (isspace(*endp)) size++;
if (size != count) diff -u -p a/drivers/video/output.c b/drivers/video/output.c --- a/drivers/video/output.c +++ b/drivers/video/output.c @@ -50,7 +50,7 @@ static ssize_t video_output_store_state( int request_state = simple_strtoul(buf,&endp,0); size_t size = endp - buf;
- if (*endp && isspace(*endp)) + if (isspace(*endp)) size++; if (size != count) return -EINVAL;
On Sat, 2009-11-07 at 13:16 -0200, André Goddard Rosa wrote:
This patch reduces lib.a code size by 173 bytes on my Core 2 with gcc 4.4.1 even considering that it exports a newly defined function skip_spaces() to drivers: text data bss dec hex filename 64867 840 592 66299 102fb (TOTALS-lib.a-before) 64954 584 588 66126 1024e (TOTALS-lib.a-after) and implements some code tidy up.
Besides reducing lib.a size, it converts many in-tree drivers to use the newly defined function, which makes another small reduction on kernel size overall when those drivers are used.
Before we embark on something as massive as this, could we take a step back. I agree that if I were coming up with the strstip() interface today I probably wouldn't have given it two overloaded uses.
However, I think the function, in spite of this minor issue, is very usable. I still don't understand why people thought adding a __must_check, which is what damaged one of the overloaded uses, is a good idea.
Assuming there's a good answer to the above:
- skip_spaces - Removes leading whitespace from @s.
- @s: The string to be stripped.
- Returns a pointer to the first non-whitespace character in @s.
- */
+const char *skip_spaces(const char *str)
I don't think const return is a good idea because most functions will be manipulating the string and using pointers that won't be const, so this will generate a ton of 'initialization discards qualifiers from pointer target type' ... so that leads to the question of whether this patch series was actually compiled ...
James
Hi, James!
On Sun, Nov 8, 2009 at 2:05 PM, James Bottomley James.Bottomley@hansenpartnership.com wrote:
On Sat, 2009-11-07 at 13:16 -0200, André Goddard Rosa wrote:
This patch reduces lib.a code size by 173 bytes on my Core 2 with gcc 4.4.1 even considering that it exports a newly defined function skip_spaces() to drivers: text data bss dec hex filename 64867 840 592 66299 102fb (TOTALS-lib.a-before) 64954 584 588 66126 1024e (TOTALS-lib.a-after) and implements some code tidy up.
Besides reducing lib.a size, it converts many in-tree drivers to use the newly defined function, which makes another small reduction on kernel size overall when those drivers are used.
Before we embark on something as massive as this, could we take a step back. I agree that if I were coming up with the strstip() interface today I probably wouldn't have given it two overloaded uses.
However, I think the function, in spite of this minor issue, is very usable. I still don't understand why people thought adding a __must_check, which is what damaged one of the overloaded uses, is a good idea.
Differently of "static void strip(char *str)"@scripts/kconfig/conf.c , this function does not moves the characters to the beginning of the string, so that if that string is going to be reused it should refer to the newly returned string start.
I've changed it to remove the const and return a "char *".
Do you think __must_check is not needed as well?
Thanks, André
participants (5)
-
Alan Cox
-
André Goddard Rosa
-
James Bottomley
-
Julia Lawall
-
Theodore Tso