From: Nick Bowler <nbowler@draconx.ca>
Date: Tue, 15 Sep 2009 02:43:49 +0000 (-0400)
Subject: package: Add initial support for package search.
X-Git-Url: https://git.draconx.ca/gitweb/upkg.git/commitdiff_plain/5a1bc015e48db57deda5a7069c26ebcd6b255441

package: Add initial support for package search.
---

diff --git a/src/package.c b/src/package.c
index afa1272..cbbaf09 100644
--- a/src/package.c
+++ b/src/package.c
@@ -31,10 +31,18 @@
 
 struct upkg_priv {
 	lt_dlhandle native;
+	FILE *pkg_file;
 };
 
 G_DEFINE_TYPE(UPkg, u_pkg, G_TYPE_TYPE_MODULE);
 
+/* Package search path. */
+static char  *search_path;
+static size_t search_path_sz;
+
+/* List of package file extensions, in descending order of precedence. */
+static const char u_pkg_exts[][5] = { ".u", ".utx", ".umx", ".uax", ".unr" };
+
 static char *str_cpy_lower(char *dst, const char *src)
 {
 	size_t i;
@@ -46,6 +54,25 @@ static char *str_cpy_lower(char *dst, const char *src)
 	return dst;
 }
 
+static int str_cmp_lower(const char *s1, const char *s2)
+{
+	size_t i;
+
+	for (i = 0; s1[i] && s2[i]; i++) {
+		int c1 = tolower(s1[i]), c2 = tolower(s2[i]);
+		if (c1 < c2)
+			return -1;
+		if (c1 > c2)
+			return 1;
+	}
+
+	if (s1[i])
+		return 1;
+	if (s2[i])
+		return -1;
+	return 0;
+}
+
 static void dl_print_errors(const char *prefix)
 {
 	const char *err;
@@ -55,6 +82,50 @@ static void dl_print_errors(const char *prefix)
 	}
 }
 
+/*
+ * Function for use with lt_dlforeachfile.  The user data must point to
+ * a UPkg with the GTypeModule name field initialized.  If a suitable file
+ * is found and could be successfully opened for reading, the pkg_file member
+ * of struct upkg_priv will be filled in.
+ */
+static int find_package_by_name(const char *filename, void *_pkg)
+{
+	struct upkg_priv *priv = U_PKG_GET_PRIV(_pkg);
+	GTypeModule *m = _pkg;
+
+	const char *base;
+	size_t len;
+	char *buf;
+
+	base = strrchr(filename, '/');
+	if (base) {
+		base++;
+	} else {
+		base = filename;
+	}
+
+	if (str_cmp_lower(base, m->name) != 0)
+		return 0;
+
+	len = strlen(filename);
+	buf = malloc(len + sizeof **u_pkg_exts);
+	if (!buf)
+		return 0;
+	strcpy(buf, filename);
+
+	for (unsigned i = 0; i < sizeof u_pkg_exts / sizeof *u_pkg_exts; i++) {
+		strcpy(buf+len, u_pkg_exts[i]);
+		priv->pkg_file = fopen(buf, "rb");
+		if (priv->pkg_file) {
+			free(buf);
+			return 1;
+		}
+	}
+
+	free(buf);
+	return 0;
+}
+
 static gboolean u_pkg_load(GTypeModule *m)
 {
 	struct upkg_priv *priv = U_PKG_GET_PRIV(m);
@@ -73,6 +144,8 @@ static gboolean u_pkg_load(GTypeModule *m)
 		return FALSE;
 	}
 
+	lt_dlforeachfile(u_pkg_get_search_path(), find_package_by_name, m);
+
 	return TRUE;
 }
 
@@ -91,6 +164,10 @@ static void u_pkg_unload(GTypeModule *m)
 			dl_print_errors(__func__);
 		}
 	}
+
+	if (priv->pkg_file) {
+		fclose(priv->pkg_file);
+	}
 }
 
 static void u_pkg_init(UPkg *pkg)
@@ -120,6 +197,55 @@ static void u_pkg_class_init(UPkgClass *class)
 	modclass->unload = u_pkg_unload;
 }
 
+static int expand_search_path(size_t need)
+{
+	size_t want = search_path_sz;
+	if (want == 0) want = 1;
+
+	while (want < need)
+		want *= 2;
+
+	if (want > search_path_sz) {
+		char *new = realloc(search_path, want);
+		if (!new) {
+			return -1;
+		}
+
+		search_path    = new;
+		search_path_sz = want;
+	}
+
+	return 0;
+}
+
+const char *u_pkg_get_search_path(void)
+{
+	return search_path ? search_path : "";
+}
+
+int u_pkg_set_search_path(const char *path)
+{
+	if (expand_search_path(strlen(path)+1) != 0)
+		return -1;
+	strcpy(search_path, path);
+	return 0;
+}
+
+int u_pkg_add_search_dir(const char *path)
+{
+	size_t end = search_path ? strlen(search_path) : 0;
+
+	if (end == 0) {
+		return u_pkg_set_search_path(path);
+	}
+
+	if (expand_search_path(end + strlen(path) + 2) != 0)
+		return -1;
+	search_path[end] = LT_PATHSEP_CHAR;
+	strcpy(search_path+end+1, path);
+	return 0;
+}
+
 GTypeModule *u_pkg_new(const char *name)
 {
 	g_return_val_if_fail(name != NULL, NULL);
diff --git a/src/uobject/package.h b/src/uobject/package.h
index e8cb4a8..697abd2 100644
--- a/src/uobject/package.h
+++ b/src/uobject/package.h
@@ -47,4 +47,8 @@ struct UPkgClass {
 GType u_pkg_get_type(void);
 GTypeModule *u_pkg_new(const char *name);
 
+const char *u_pkg_get_search_path(void);
+int u_pkg_set_search_path(const char *path);
+int u_pkg_add_search_dir(const char *path);
+
 #endif