1 files changed, 50 insertions, 0 deletions
diff --git a/src/compgen.c b/src/compgen.c
new file mode 100644
index 0000000..e04e0a5
--- /dev/null
+++ b/src/compgen.c
@@ -0,0 +1,50 @@
+#include <dirent.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include "log.h"
+#include "string_vec.h"
+
+struct string_vec compgen()
+{
+	log_debug("Retrieving PATH.\n");
+	const char *env_path = getenv("PATH");
+	if (env_path == NULL) {
+		log_error("Couldn't retrieve PATH from environment.");
+		exit(EXIT_FAILURE);
+	}
+	struct string_vec programs = string_vec_create();
+	char *path = strdup(env_path);
+	char *saveptr = NULL;
+	char *path_entry = strtok_r(path, ":", &saveptr);
+	log_debug("Scanning PATH for binaries.\n");
+	while (path_entry != NULL) {
+		DIR *dir = opendir(path_entry);
+		if (dir != NULL) {
+			int fd = dirfd(dir);
+			struct dirent *d;
+			while ((d = readdir(dir)) != NULL) {
+				struct stat sb;
+				if (fstatat(fd, d->d_name, &sb, 0) == -1) {
+					continue;
+				}
+				if (!(sb.st_mode & S_IXUSR)) {
+					continue;
+				}
+				if (!S_ISREG(sb.st_mode)) {
+					continue;
+				}
+				string_vec_add(&programs, d->d_name);
+			}
+			closedir(dir);
+		}
+		path_entry = strtok_r(NULL, ":", &saveptr);
+	}
+	free(path);
+	log_debug("Sorting results.\n");
+	string_vec_sort(&programs);
+	log_debug("Making unique.\n");
+	string_vec_uniq(&programs);
+	log_debug("Done.\n");
+	return programs;
+}