add logic for finding -Ldirectories and -llibraries

2 files changed, 29 insertions, 12 deletions

diff --git a/cc.c b/cc.c
index 409ec2f..cb07fa9 100644
--- a/cc.c
+++ b/cc.c
@@ -96,8 +96,6 @@ int main(int argc, char *argv[])
 
 	struct macro *predef = do_predefs(argv[0]);
 
-	addlibdir("/lib/x86_64-linux-gnu", 0);
-
 	for (int i = 1; i < argc; i++) {
 		if (!strcmp(argv[i], "-c")) {
 			output = OBJECT;
diff --git a/libs.c b/libs.c
index e9ad7ae..c5272e3 100644
--- a/libs.c
+++ b/libs.c
@@ -11,29 +11,48 @@
 #include "cc.h"
 #include "libs.h"
 
-static char **libdirs = NULL;
-static size_t nlibdirs = 0;
+
+static char *system_dirs[] = {
+	"/lib/x86_64-linux-gnu",
+	"/usr/lib/x86_64-linux-gnu",
+	"/usr/local/lib/x86_64-linux-gnu",
+};
+static size_t nsystem_dirs = sizeof(system_dirs) / sizeof(system_dirs[0]);
+
+static char **user_dirs = NULL;
+static size_t nuser_dirs = 0;
 
 void addlibdir(char *path, int commandline)
 {
-	libdirs = realloc(libdirs, (nlibdirs + 1) * sizeof(*libdirs));
-	if (!libdirs) {
+	user_dirs = realloc(user_dirs, (nuser_dirs + 1) * sizeof(*user_dirs));
+	if (!user_dirs) {
 		error(NULL, commandline, "out of memory adding '%s' to library search path\n", path);
 	}
-	libdirs[nlibdirs++] = path;
+	user_dirs[nuser_dirs++] = path;
 }
 
-char *findlib(const char *lib)
+static char *do_findlib(size_t ndirs, char *dirs[static ndirs], size_t plen, char path[static plen], const char *lib)
 {
-	char path[PATH_MAX];
-	for (size_t i = 0; i < nlibdirs; i++) {
-		snprintf(path, sizeof(path), "-l%s/lib%s.a", libdirs[i], lib);
+	for (size_t i = 0; i < ndirs; i++) {
+		snprintf(path, plen, "-l%s/lib%s.a", dirs[i], lib);
 		printf("checking %s\n", path + 2);
 		if (access(path + 2, F_OK) == 0) {
 			printf("\tOK\n");
-			return strdup(path);
+			return path;
 		}
 	}
+	return NULL;
+}
+
+char *findlib(const char *lib)
+{
+	static char path[PATH_MAX];
+	if (do_findlib(nsystem_dirs, system_dirs, sizeof(path), path, lib)) {
+		return path;
+	}
+	if (do_findlib(nuser_dirs, user_dirs, sizeof(path), path, lib)) {
+		return path;
+	}
 	error(NULL, 1, "could not find library -l%s\n", lib);
 	return NULL;
 }