Fix various Windows related path issues

src/foundation/platform.h

@@ -1,78 +1,108 @@
-/*
- * platform.h — OS abstractions.
- *
- * Provides cross-platform wrappers for:
- *   - Memory-mapped files (mmap / VirtualAlloc)
- *   - High-resolution monotonic clock
- *   - CPU core count
- *   - File existence check
- */
-#ifndef CBM_PLATFORM_H
-#define CBM_PLATFORM_H
-
-#include <stddef.h>
-#include <stdint.h>
-#include <stdbool.h>
-#include <stdlib.h>
-
-/* ── Safe memory ──────────────────────────────────────────────── */
-
-/* Safe realloc: frees old pointer on failure instead of leaking it.
- * Returns NULL on allocation failure (old memory is freed). */
-static inline void *safe_realloc(void *ptr, size_t size) {
-    void *tmp = realloc(ptr, size); // NOLINT(clang-analyzer-optin.portability.UnixAPI)
-    if (!tmp) {
-        free(ptr);
-    }
-    return tmp;
-}
-
-/* ── Memory mapping ────────────────────────────────────────────── */
-
-/* Map a file read-only into memory. Returns NULL on error.
- * *out_size is set to the file size. */
-void *cbm_mmap_read(const char *path, size_t *out_size);
-
-/* Unmap a previously mapped region. */
-void cbm_munmap(void *addr, size_t size);
-
-/* ── Timing ────────────────────────────────────────────────────── */
-
-/* Monotonic nanosecond timestamp (for elapsed time measurement). */
-uint64_t cbm_now_ns(void);
-
-/* Monotonic millisecond timestamp. */
-uint64_t cbm_now_ms(void);
-
-/* ── System info ───────────────────────────────────────────────── */
-
-/* Number of available CPU cores. */
-int cbm_nprocs(void);
-
-/* System topology: core types and RAM (only fields with production consumers). */
-typedef struct {
-    int total_cores;  /* hw.ncpu (all cores) */
-    int perf_cores;   /* P-cores (Apple) or total_cores (others) */
-    size_t total_ram; /* total physical RAM in bytes */
-} cbm_system_info_t;
-
-/* Query system information. Results are cached after first call. */
-cbm_system_info_t cbm_system_info(void);
-
-/* Recommended worker count for parallel indexing.
- * initial=true:  all cores (user is waiting for initial index)
- * initial=false: max(1, perf_cores-1) (leave headroom for user apps) */
-int cbm_default_worker_count(bool initial);
-
-/* ── File system ───────────────────────────────────────────────── */
-
-/* Check if a path exists. */
-bool cbm_file_exists(const char *path);
-
-/* Check if path is a directory. */
-bool cbm_is_dir(const char *path);
-
-/* Get file size. Returns -1 on error. */
-int64_t cbm_file_size(const char *path);
-
-#endif /* CBM_PLATFORM_H */
+/*
+ * platform.h — OS abstractions.
+ *
+ * Provides cross-platform wrappers for:
+ *   - Memory-mapped files (mmap / VirtualAlloc)
+ *   - High-resolution monotonic clock
+ *   - CPU core count
+ *   - File existence check
+ */
+#ifndef CBM_PLATFORM_H
+#define CBM_PLATFORM_H
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <stdlib.h>
+
+/* ── Safe memory ──────────────────────────────────────────────── */
+
+/* Safe realloc: frees old pointer on failure instead of leaking it.
+ * Returns NULL on allocation failure (old memory is freed). */
+static inline void *safe_realloc(void *ptr, size_t size) {
+    void *tmp = realloc(ptr, size); // NOLINT(clang-analyzer-optin.portability.UnixAPI)
+    if (!tmp) {
+        free(ptr);
+    }
+    return tmp;
+}
+
+/* ── Memory mapping ────────────────────────────────────────────── */
+
+/* Map a file read-only into memory. Returns NULL on error.
+ * *out_size is set to the file size. */
+void *cbm_mmap_read(const char *path, size_t *out_size);
+
+/* Unmap a previously mapped region. */
+void cbm_munmap(void *addr, size_t size);
+
+/* ── Timing ────────────────────────────────────────────────────── */
+
+/* Monotonic nanosecond timestamp (for elapsed time measurement). */
+uint64_t cbm_now_ns(void);
+
+/* Monotonic millisecond timestamp. */
+uint64_t cbm_now_ms(void);
+
+/* ── System info ───────────────────────────────────────────────── */
+
+/* Number of available CPU cores. */
+int cbm_nprocs(void);
+
+/* System topology: core types and RAM (only fields with production consumers). */
+typedef struct {
+    int total_cores;  /* hw.ncpu (all cores) */
+    int perf_cores;   /* P-cores (Apple) or total_cores (others) */
+    size_t total_ram; /* total physical RAM in bytes */
+} cbm_system_info_t;
+
+/* Query system information. Results are cached after first call. */
+cbm_system_info_t cbm_system_info(void);
+
+/* Recommended worker count for parallel indexing.
+ * initial=true:  all cores (user is waiting for initial index)
+ * initial=false: max(1, perf_cores-1) (leave headroom for user apps) */
+int cbm_default_worker_count(bool initial);
+
+/* ── File system ───────────────────────────────────────────────── */
+
+/* Check if a path exists. */
+bool cbm_file_exists(const char *path);
+
+/* Check if path is a directory. */
+bool cbm_is_dir(const char *path);
+
+/* Get the user's home directory.
+ * POSIX: returns HOME. Windows: returns HOME, then USERPROFILE.
+ * Path is normalized to forward slashes.
+ * Returns static buffer — do NOT free. Returns NULL on failure. */
+const char *cbm_home_dir(void);
+
+/* Get the application config directory.
+ * macOS: returns HOME (caller appends "Library/Application Support/App/...").
+ * Linux: returns XDG_CONFIG_HOME or HOME/.config (caller appends "app/...").
+ * Windows: returns APPDATA, e.g. "C:/Users/x/AppData/Roaming" (caller appends "App/...").
+ * Path is normalized to forward slashes.
+ * Returns static buffer — do NOT free. Returns NULL on failure. */
+const char *cbm_app_config_dir(void);
+
+/* Get the application local data directory.
+ * macOS/Linux: same as cbm_app_config_dir().
+ * Windows: returns LOCALAPPDATA, e.g. "C:/Users/x/AppData/Local" (caller appends "App/...").
+ * Path is normalized to forward slashes.
+ * Returns static buffer — do NOT free. Returns NULL on failure. */
+const char *cbm_app_local_dir(void);
+
+/* Get the absolute path of the currently running executable.
+ * Returns static buffer — do NOT free. Returns "" on failure. */
+const char *cbm_self_exe_path(void);
+
+/* Normalize path separators to forward slashes (in-place).
+ * On Windows, converts backslashes to forward slashes.
+ * On POSIX, this is a no-op. Returns the input pointer. */
+char *cbm_normalize_path_sep(char *path);
+
+/* Get file size. Returns -1 on error. */
+int64_t cbm_file_size(const char *path);
+
+#endif /* CBM_PLATFORM_H */