diff options
Diffstat (limited to 'libopts/compat/strchr.c')
-rw-r--r-- | libopts/compat/strchr.c | 60 |
1 files changed, 60 insertions, 0 deletions
diff --git a/libopts/compat/strchr.c b/libopts/compat/strchr.c new file mode 100644 index 0000000000..413f999ff9 --- /dev/null +++ b/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 */ |