copy from intranet.

libopts/compat/strchr.c

@@ -0,0 +1,60 @@
+/*
+   SYNOPSIS
+       #include <string.h>
+
+       char *strchr(char const *s, int c);
+
+       char *strrchr(char const *s, int c);
+
+   DESCRIPTION
+       The  strchr() function returns a pointer to the first occurrence of the
+       character c in the string s.
+
+       The strrchr() function returns a pointer to the last occurrence of  the
+       character c in the string s.
+
+       Here  "character"  means "byte" - these functions do not work with wide
+       or multi-byte characters.
+
+   RETURN VALUE
+       The strchr() and strrchr() functions return a pointer  to  the  matched
+       character or NULL if the character is not found.
+
+   CONFORMING TO
+       SVID 3, POSIX, BSD 4.3, ISO 9899
+*/
+
+char*
+strchr( char const *s, int c)
+{
+    do {
+        if ((unsigned)*s == (unsigned)c)
+            return s;
+
+    } while (*(++s) != NUL);
+
+    return NULL;
+}
+
+char*
+strrchr( char const *s, int c)
+{
+    char const *e = s + strlen(s);
+
+    for (;;) {
+        if (--e < s)
+            break;
+
+        if ((unsigned)*e == (unsigned)c)
+            return e;
+    }
+    return NULL;
+}
+
+/*
+ * Local Variables:
+ * mode: C
+ * c-file-style: "stroustrup"
+ * indent-tabs-mode: nil
+ * End:
+ * end of compat/strsignal.c */