libreplace: some systems don't have memmem()

[samba.git] / lib / replace / replace.c

diff --git a/lib/replace/replace.c b/lib/replace/replace.c
index fc15717349e1d189dcd9494d1bc2dd61e12ca92c..17fd46bcc89828b5bd85ce7573c68fafe106c04c 100644 (file)
--- a/lib/replace/replace.c
+++ b/lib/replace/replace.c
@@ -681,3 +681,26 @@ char *rep_realpath(const char *path, char *resolved_path)
        return NULL;
 }
 #endif
+
+
+#ifndef HAVE_MEMMEM
+void *rep_memmem(const void *haystack, size_t haystacklen,
+                const void *needle, size_t needlelen)
+{
+       if (needlelen == 0) {
+               return discard_const(haystack);
+       }
+       while (haystacklen >= needlelen) {
+               char *p = memchr(haystack, *(const char *)needle,
+                                haystacklen-(needlelen-1));
+               if (!p) return NULL;
+               if (memcmp(p, needle, needlelen) == 0) {
+                       return p;
+               }
+               haystack = p+1;
+               haystacklen -= (p - (const char *)haystack) + 1;
+       }
+       return NULL;
+}
+#endif
+