feature: enhance current working directory functions for improved error handling and memory management

Source/DrangPlatform/Include/drang/fs.h

@@ -509,12 +509,12 @@ DRANG_PLATFORM_API int drang_fs_closedir(drang_fs_directory_t *directory);
  * Retrieves the absolute path of the current working directory.
  * The path is null-terminated and stored in the provided buffer.
  *
- * @param[out] buffer Buffer to receive the current working directory path.
- * @param[in] size Size of the buffer in bytes.
+ * @param[out] buffer Buffer to receive the current working directory path. (may be NULL)
+ * @param[in] size Size of the buffer in bytes. (must be > 0 if buffer is not NULL)
  * @param[out] out_size Pointer to store the actual path length (may be NULL).
  * @return 0 on success, negative error code on failure.
  * @retval DRANG_EOK Success - current directory retrieved successfully.
- * @retval DRANG_EINVAL Invalid parameter (buffer is NULL or size is 0).
+ * @retval DRANG_EINVAL Invalid parameter (buffer is NULL or size is not 0 or buffer is not NULL and size is 0).
  * @retval DRANG_ENOMEM Buffer too small to hold the path.
  * @retval DRANG_EIO I/O error occurred during path retrieval.
  * @remarks If out_size is provided, it contains the required buffer size on DRANG_ENOMEM.

Source/DrangPlatform/Source/linux/fs/dir.c

@@ -7,6 +7,7 @@
 #include <fcntl.h>
 #include <string.h>
 #include <sys/stat.h>
+#include <stdlib.h>
 
 int drang_fs_mkdir(const char *path, drang_fs_permissions_t permissions)
 {
@@ -128,17 +129,26 @@ int drang_fs_closedir(drang_fs_directory_t *directory)
 int drang_fs_get_cwd(char *buffer, size_t size, size_t *out_size)
 {
     DRANG_BEGIN_TRY()
-    DRANG_FAIL_IF_NULL(buffer, DRANG_EINVAL);
-    if (getcwd(buffer, size) != NULL) {
-        DRANG_RETURN_IN(out_size, strlen(buffer));
-    }
-
-    if (errno == ERANGE) {
-        if (out_size) {
-            long required_size = pathconf(".", _PC_PATH_MAX);
-            *out_size = required_size;
+    DRANG_CHECK((buffer != NULL && size > 0) || (buffer == NULL && size == 0), DRANG_EINVAL);
+    char* dir = get_current_dir_name();
+    if (dir != NULL) {
+        const size_t dir_length = strlen(dir);
+        if (buffer != NULL && size < dir_length + 1) {
+            free(dir);
+            if (out_size) {
+                *out_size = dir_length;
+            }
+            DRANG_FAIL(DRANG_ENOMEM);
         }
-        DRANG_FAIL(DRANG_ENOMEM);
+        if (buffer != NULL) {
+            memcpy(buffer, dir, dir_length);
+            buffer[dir_length] = '\0';
+        }
+        free(dir);
+        if (out_size) {
+            *out_size = dir_length + 1;
+        }
+        DRANG_RETURN();
     }
 
     DRANG_FAIL(drang_errno_to_error(errno));
@@ -149,6 +159,7 @@ int drang_fs_get_cwd(char *buffer, size_t size, size_t *out_size)
 int drang_fs_set_cwd(const char *path)
 {
     DRANG_BEGIN_TRY()
+    DRANG_CHECK(path != NULL, DRANG_EINVAL);
 
     if (chdir(path) != 0) {
         DRANG_FAIL(drang_errno_to_error(errno));

Source/DrangPlatform/Source/win32/fs/dir.c

@@ -125,9 +125,8 @@ int drang_fs_get_cwd(char *buffer, size_t size, size_t *out_size)
 {
     DWORD length = 0;
     DRANG_BEGIN_TRY()
-    DRANG_FAIL_IF_NULL(buffer, DRANG_EINVAL);
 
-    length = GetCurrentDirectoryA((DWORD) size, buffer);
+    length = GetCurrentDirectoryA(buffer ? (DWORD) size : 0, buffer);
     if (length == 0) {
         DRANG_FAIL(win32_error_to_drang(GetLastError()));
     }