add strstarts strends strcasestarts strcaseends wcsstarts wcsends wcscasestarts wcscaseends

Signed-off-by: Mattias Andrée <maandree@operamail.com>

5 files changed, 280 insertions, 3 deletions

diff --git a/TODO b/TODO
index 4f893ff..c376ec1 100644
--- a/TODO
+++ b/TODO
@@ -16,6 +16,3 @@ input/output overview  (15 p429)
 debugging support  (16 p435)
 input/output on streams  (17 p439)
 
-add strstarts, strends, wcsstarts, wcsends as
-  faster specialised alternatives to strstr.
-
diff --git a/include/string.h b/include/string.h
index b851a76..08777be 100644
--- a/include/string.h
+++ b/include/string.h
@@ -969,6 +969,62 @@ char* rawstrcasestr(const char*, const char*)
  */
 void* memcasemem(const void*, size_t, const void*, size_t)
   __GCC_ONLY(__attribute__((warn_unused_result, pure)));
+
+/**
+ * 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*, const char*)
+  __GCC_ONLY(__attribute__((warn_unused_result, nonnull, pure)));
+
+/**
+ * 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*, const char*)
+  __GCC_ONLY(__attribute__((warn_unused_result, nonnull, pure)));
+
+/**
+ * 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*, const char*)
+  __GCC_ONLY(__attribute__((warn_unused_result, nonnull, pure)));
+
+/**
+ * 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*, const char*)
+  __GCC_ONLY(__attribute__((warn_unused_result, nonnull, pure)));
 #endif
 
 #if (defined(_GNU_SOURCE) || defined(_SLIBC_SOURCE)) && !defined(__PORTABLE)
diff --git a/include/wchar.h b/include/wchar.h
index 9b57a7e..e9d2daa 100644
--- a/include/wchar.h
+++ b/include/wchar.h
@@ -942,6 +942,62 @@ wchar_t* rawwcscasestr(const wchar_t*, const wchar_t*)
  */
 wchar_t* wmemcasemem(const wchar_t*, size_t, const wchar_t*, size_t)
   __GCC_ONLY(__attribute__((warn_unused_result, pure)));
+
+/**
+ * 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.
+ */
+wchar_t* wcsstarts(const wchar_t*, const wchar_t*)
+  __GCC_ONLY(__attribute__((warn_unused_result, nonnull, pure)));
+
+/**
+ * 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.
+ */
+wchar_t* wcsends(const wchar_t*, const wchar_t*)
+  __GCC_ONLY(__attribute__((warn_unused_result, nonnull, pure)));
+
+/**
+ * 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.
+ */
+wchar_t* wcscasestarts(const wchar_t*, const wchar_t*)
+  __GCC_ONLY(__attribute__((warn_unused_result, nonnull, pure)));
+
+/**
+ * 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.
+ */
+wchar_t* wcscaseends(const wchar_t*, const wchar_t*)
+  __GCC_ONLY(__attribute__((warn_unused_result, nonnull, pure)));
 #endif
 
 #if (defined(_GNU_SOURCE) || defined(_SLIBC_SOURCE)) && !defined(__PORTABLE)
diff --git a/src/string/strstr.c b/src/string/strstr.c
index d63628a..34b3120 100644
--- a/src/string/strstr.c
+++ b/src/string/strstr.c
@@ -182,3 +182,87 @@ void* memcasemem(const void* __haystack, size_t haystack_length,
 #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);
+}
+
diff --git a/src/wchar/wcsstr.c b/src/wchar/wcsstr.c
index f54ff6e..bc2bbec 100644
--- a/src/wchar/wcsstr.c
+++ b/src/wchar/wcsstr.c
@@ -192,3 +192,87 @@ wchar_t* wmemcasemem(const wchar_t* haystack, size_t haystack_length,
 #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.
+ */
+wchar_t* wcsstarts(const wchar_t* string, const wchar_t* desired)
+{
+  size_t n = wcslen(string);
+  size_t m = wcslen(desired);
+  if (n < m)
+    return NULL;
+  return wmemcmp(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.
+ */
+wchar_t* wcsends(const wchar_t* string, const wchar_t* desired)
+{
+  size_t n = wcslen(string);
+  size_t m = wcslen(desired);
+  if (n < m)
+    return NULL;
+  return wmemcmp(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.
+ */
+wchar_t* wcscasestarts(const wchar_t* string, const wchar_t* desired)
+{
+  size_t n = wcslen(string);
+  size_t m = wcslen(desired);
+  if (n < m)
+    return NULL;
+  return wmemcasecmp(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.
+ */
+wchar_t* wcscaseends(const wchar_t* string, const wchar_t* desired)
+{
+  size_t n = wcslen(string);
+  size_t m = wcslen(desired);
+  if (n < m)
+    return NULL;
+  return wmemcasecmp(string + (n - m), desired, m) ? NULL : (string + n);
+}
+