pkg: add pkg_scan() and pkg_scan_all() functions.

pkg.c

@@ -274,6 +274,66 @@ pkg_try_specific_path(const char *path, const char *name, unsigned int flags)
 	return pkg;
 }
 
+static void
+pkg_scan_dir(const char *path, pkg_iteration_func_t func)
+{
+	DIR *dir;
+	struct dirent *dirent;
+
+	dir = opendir(path);
+	if (dir == NULL)
+		return;
+
+	for (dirent = readdir(dir); dirent != NULL; dirent = readdir(dir))
+	{
+		pkg_t *pkg;
+		FILE *f;
+
+		f = fopen(dirent->d_name, "r");
+		if (f == NULL)
+			continue;
+
+		pkg = pkg_new_from_file(dirent->d_name, f);
+		if (pkg != NULL)
+			func(pkg);
+	}
+
+	closedir(dir);
+}
+
+void
+pkg_scan(const char *search_path, pkg_iteration_func_t func)
+{
+	char **path = NULL;
+	size_t count = 0, iter = 0;
+
+	/* PKG_CONFIG_PATH has to take precedence */
+	if (search_path == NULL)
+		return;
+
+	count = path_split(search_path, &path);
+
+	for (iter = 0; iter < count; iter++)
+		pkg_scan_dir(path[iter], func);
+
+	path_free(path, count);
+}
+
+void
+pkg_scan_all(pkg_iteration_func_t func)
+{
+	char *path;
+
+	path = getenv("PKG_CONFIG_PATH");
+	if (path)
+	{
+		pkg_scan_dir(path, func);
+		return;
+	}
+
+	pkg_scan_dir(get_pkgconfig_path(), func);
+}
+
 #ifdef _WIN32
 pkg_t *
 pkg_find_in_registry_key(HKEY hkey, const char *name, unsigned int flags)

pkg.h

@@ -114,11 +114,14 @@ struct pkg_ {
 #define PKG_ERRF_PACKAGE_VER_MISMATCH	0x2
 #define PKG_ERRF_PACKAGE_CONFLICT	0x4
 
+typedef void (*pkg_iteration_func_t)(const pkg_t *pkg);
 typedef void (*pkg_traverse_func_t)(pkg_t *pkg, void *data, unsigned int flags);
 
 /* pkg.c */
 void pkg_free(pkg_t *pkg);
 pkg_t *pkg_find(const char *name, unsigned int flags);
+void pkg_scan(const char *search_path, pkg_iteration_func_t func);
+void pkg_scan_all(pkg_iteration_func_t func);
 unsigned int pkg_traverse(pkg_t *root, pkg_traverse_func_t func, void *data, int maxdepth, unsigned int flags);
 unsigned int pkg_verify_graph(pkg_t *root, int depth, unsigned int flags);
 int pkg_compare_version(const char *a, const char *b);

stdinc.h

@@ -23,6 +23,7 @@
 #include <stdbool.h>
 #include <string.h>
 #include <libgen.h>
+#include <dirent.h>
 
 #ifdef _WIN32
 # define WIN32_LEAN_AND_MEAN