internal/bytealg: support systems that don't have memmem

Reviewed-on: https://go-review.googlesource.com/138839

From-SVN: r264798
This commit is contained in:
Ian Lance Taylor 2018-10-02 16:45:51 +00:00
parent 3c609d36a6
commit d8ccfadbf2
5 changed files with 33 additions and 3 deletions

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@ -1,4 +1,4 @@
098e36f4ddfcf50aeb34509b5f25b86d7050749c
bde5ac90e0b4efdf3e9a4d72af4eb23250608611
The first line of this file holds the git revision number of the last
merge done from the gofrontend repository.

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@ -141,6 +141,9 @@
/* Define to 1 if you have the `matherr' function. */
#undef HAVE_MATHERR
/* Define to 1 if you have the `memmem' function. */
#undef HAVE_MEMMEM
/* Define to 1 if you have the <memory.h> header file. */
#undef HAVE_MEMORY_H

2
libgo/configure vendored
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@ -14781,7 +14781,7 @@ else
fi
for ac_func in strerror_r strsignal wait4 mincore setenv unsetenv dl_iterate_phdr
for ac_func in strerror_r strsignal wait4 mincore setenv unsetenv dl_iterate_phdr memmem
do :
as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"

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@ -544,7 +544,7 @@ AC_CHECK_HEADERS([linux/filter.h linux/if_addr.h linux/if_ether.h linux/if_tun.h
AM_CONDITIONAL(HAVE_SYS_MMAN_H, test "$ac_cv_header_sys_mman_h" = yes)
AC_CHECK_FUNCS(strerror_r strsignal wait4 mincore setenv unsetenv dl_iterate_phdr)
AC_CHECK_FUNCS(strerror_r strsignal wait4 mincore setenv unsetenv dl_iterate_phdr memmem)
AM_CONDITIONAL(HAVE_STRERROR_R, test "$ac_cv_func_strerror_r" = yes)
AM_CONDITIONAL(HAVE_WAIT4, test "$ac_cv_func_wait4" = yes)

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@ -10,6 +10,33 @@
#include "runtime.h"
#include "array.h"
#ifndef HAVE_MEMMEM
#define memmem goMemmem
static const void *goMemmem(const void *in, size_t inl, const void *s, size_t sl) {
const char *p;
char first;
const char *stop;
if (sl == 0) {
return in;
}
if (inl < sl) {
return nil;
}
first = *(const char *)(s);
stop = (const char *)(in) + (inl - sl);
for (p = (const char *)(in); p <= stop; p++) {
if (*p == first && __builtin_memcmp(p + 1, (const char *)(s) + 1, sl - 1) == 0) {
return (const void *)(p);
}
}
return nil;
}
#endif
intgo Compare(struct __go_open_array, struct __go_open_array)
__asm__(GOSYM_PREFIX "internal_bytealg.Compare")
__attribute__((no_split_stack));