str_extra.c

commit 428ad56e3dee370731c208a6cced4c51365ea108
parent aae4c2aad5fdad94f02d4373a79df3237d77af45
Author: finwo <finwo@pm.me>
Date:   Fri, 10 Apr 2026 20:25:54 +0200

Add readme, rename config.mk to export.mk

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README.md
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config.mk -> export.mk
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2 files changed, 39 insertions(+), 0 deletions(-)
diff --git a/README.md b/README.md
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+# c-strextra
+
+A lightweight C library providing additional string utility functions.
+
+## Functions
+
+### `str_isHex(const char *subject)`
+Checks if a string contains only hexadecimal characters (0-9, a-f, A-F).
+Returns `true` if all characters are hex digits, `false` otherwise.
+
+### `strnstr(const char *haystack, const char *needle, size_t len)`
+Finds the first occurrence of a substring in a string with a length limit.
+Similar to `strstr()` but only searches the first `len` characters.
+Returns a pointer to the found substring or `NULL` if not found.
+
+### `strtoupper(char *str)`
+Converts all characters in a string to uppercase.
+Modifies the input string in-place and returns a pointer to it.
+
+### `strcasecmp(const char *a, const char *b)`
+Case-insensitive string comparison.
+On Windows (where this function may not be available), provides a custom implementation.
+Returns 0 if strings are equal (case-insensitive), negative if `a < b`, positive if `a > b`.
+
+## Usage
+
+Include the main header file:
+
+```c
+#include "str_extra.h"
+```
+
+Or include individual headers for specific functions.
+
+## Platform Support
+
+- Works on POSIX systems (Linux, macOS) and Windows
+- `strcasecmp` uses system implementation where available, provides fallback for Windows
+- Standard C library dependencies: `<ctype.h>`, `<string.h>`, `<stdlib.h>`, `<stdbool.h>`
diff --git a/config.mk b/export.mk