/**
* slibc — Yet another C library
* Copyright © 2015 Mattias Andrée (maandree@member.fsf.org)
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include <string.h>
#include <stdint.h>
#include <unistd.h>
#include <alloca.h>
#include <ctype.h>
# pragma GCC diagnostic ignored "-Wdiscarded-qualifiers"
/**
* Finds the first occurrence of a substring.
* This search is case sensitive.
*
* @param haystack The string to search.
* @param needle The sought after substring.
* @return Pointer to the first occurrence of the
* substring, `NULL` if not found.
*/
char* strstr(const char* haystack, const char* needle)
{
return memmem(haystack, strlen(haystack), needle, strlen(needle));
}
/**
* Finds the first occurrence of a substring.
* This search is case insensitive.
*
* @param haystack The string to search.
* @param needle The sought after substring.
* @return Pointer to the first occurrence of the
* substring, `NULL` if not found.
*/
char* strcasestr(const char* haystack, const char* needle)
{
return memcasemem(haystack, strlen(haystack), needle, strlen(needle));
}
/**
* Finds the first occurrence of a substring.
* This search is case sensitive.
*
* This is a slibc extension added for because it was useful
* in implementing slibc itself.
*
* @param haystack The string to search.
* @param needle The sought after substring.
* @param maxlen The maximum number of character to search.
* @return Pointer to the first occurrence of the
* substring, `NULL` if not found.
*/
char* strnstr(const char* haystack, const char* needle, size_t maxlen)
{
return memmem(haystack, strnlen(haystack, maxlen), needle, strlen(needle));
}
/**
* Finds the first occurrence of a substring.
* This search is case insensitive.
*
* This is a slibc extension added for completeness.
*
* @param haystack The string to search.
* @param needle The sought after substring.
* @param maxlen The maximum number of character to search.
* @return Pointer to the first occurrence of the
* substring, `NULL` if not found.
*/
char* strncasestr(const char* haystack, const char* needle, size_t maxlen)
{
return memcasemem(haystack, strnlen(haystack, maxlen), needle, strlen(needle));
}
/**
* Finds the first occurrence of a substring.
* This search is case sensitive.
* It must already be known that such a substring exists.
*
* This is a slibc extension.
*
* @param haystack The string to search.
* @param needle The sought after substring.
* @return Pointer to the first occurrence of the substring.
*/
char* rawstrstr(const char* haystack, const char* needle)
{
return memmem(haystack, SIZE_MAX, needle, strlen(needle));
}
/**
* Finds the first occurrence of a substring.
* This search is case insensitive.
* It must already be known that such a substring exists.
*
* This is a slibc extension.
*
* @param haystack The string to search.
* @param needle The sought after substring.
* @return Pointer to the first occurrence of the substring.
*/
char* rawstrcasestr(const char* haystack, const char* needle)
{
return memcasemem(haystack, SIZE_MAX, needle, strlen(needle));
}
/**
* Finds the first occurrence of a substring.
* This search is case sensitive.
*
* This is a GNU-compliant slibc extension. It was useful
* in implementing slibc itself.
*
* @param haystack The string to search.
* @param haystack_length The number of character to search.
* @param needle The sought after substring.
* @param needle_length The length of `needle`.
* @return Pointer to the first occurrence of
* the substring, `NULL` if not found.
*/
void* memmem(const void* __haystack, size_t haystack_length,
const void* __needle, size_t needle_length)
{
const char* haystack = __haystack;
const char* needle = __needle;
if (haystack_length < needle_length)
return NULL;
if (haystack_length == needle_length)
return !memcmp(haystack, needle, haystack_length) ? haystack : NULL;
#include "substring.h"
}
/**
* Finds the first occurrence of a substring.
* This search is case insensitive.
*
* This is a slibc extension added because it was useful
* in implementing slibc itself.
*
* @param haystack The string to search.
* @param haystack_length The number of character to search.
* @param needle The sought after substring.
* @param needle_length The length of `needle`.
* @return Pointer to the first occurrence of
* the substring, `NULL` if not found.
*/
void* memcasemem(const void* __haystack, size_t haystack_length,
const void* __needle, size_t needle_length)
{
const char* haystack = __haystack;
const char* needle = __needle;
if (haystack_length < needle_length)
return NULL;
if (haystack_length == needle_length)
return !memcasecmp(haystack, needle, haystack_length) ? haystack : NULL;
#define CASE
#include "substring.h"
#undef CASE
}
/**
* Check whether a string starts with a specific string.
* This check is case sensitive.
*
* This is a slibc extension.
*
* @param string The string to inspect.
* @param desired The desired beginning of the string.
* @return `string` if `string` begins with
* `desired`, `NULL` otherwise.
*/
char* strstarts(const char* string, const char* desired)
{
size_t n = strlen(string);
size_t m = strlen(desired);
if (n < m)
return NULL;
return memcmp(string, desired, m) ? NULL : string;
}
/**
* Check whether a string ends with a specific string.
* This check is case sensitive.
*
* This is a slibc extension.
*
* @param string The string to inspect.
* @param desired The desired ending of the string.
* @return The `string`, where `desired` beings if
* `string` ends with `desired`, `NULL` otherwise.
*/
char* strends(const char* string, const char* desired)
{
size_t n = strlen(string);
size_t m = strlen(desired);
if (n < m)
return NULL;
return memcmp(string + (n - m), desired, m) ? NULL : (string + n);
}
/**
* Check whether a string starts with a specific string.
* This check is case insensitive.
*
* This is a slibc extension.
*
* @param string The string to inspect.
* @param desired The desired beginning of the string.
* @return `string` if `string` begins with
* `desired`, `NULL` otherwise.
*/
char* strcasestarts(const char* string, const char* desired)
{
size_t n = strlen(string);
size_t m = strlen(desired);
if (n < m)
return NULL;
return memcasecmp(string, desired, m) ? NULL : string;
}
/**
* Check whether a string ends with a specific string.
* This check is case insensitive.
*
* This is a slibc extension.
*
* @param string The string to inspect.
* @param desired The desired ending of the string.
* @return The `string`, where `desired` beings if
* `string` ends with `desired`, `NULL` otherwise.
*/
char* strcaseends(const char* string, const char* desired)
{
size_t n = strlen(string);
size_t m = strlen(desired);
if (n < m)
return NULL;
return memcasecmp(string + (n - m), desired, m) ? NULL : (string + n);
}
