1 files changed, 81 insertions, 0 deletions
diff --git a/snag/pkg_db.c b/snag/pkg_db.c
new file mode 100644
index 0000000..26e972d
--- /dev/null
+++ b/snag/pkg_db.c
@@ -0,0 +1,81 @@
+#include "pkg_db.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#define PKG_DB "../packages"
+#define PKG_INFO_CMD "./get_pkg_attrs.sh"
+
+bool load_package_info(package_info_t* info, char* pkgid) {
+
+	// construct package description directory path and ensure it exists
+	size_t pkg_dir_len = strlen(PKG_DB) + strlen(pkgid) + 1;
+	char* pkg_dir = malloc(pkg_dir_len + 1);
+	snprintf(pkg_dir, pkg_dir_len + 1, "%s/%s", PKG_DB, pkgid);
+	if (access(pkg_dir, F_OK) != 0) {
+        fprintf(stderr, "Package '%s' not found in database\n", pkgid);
+		free(pkg_dir);
+		return false;
+    }
+
+	// construct package description script path and ensure it exists
+	size_t script_path_len = pkg_dir_len + strlen(pkgid) + 4;
+	info->script_path = malloc(script_path_len + 1);
+	snprintf(info->script_path, script_path_len + 1, "%s/%s.sh", pkg_dir, pkgid);
+	free(pkg_dir);
+	if (access(info->script_path, F_OK) != 0) {
+        fprintf(stderr, "Package '%s' broken, doesn't have description script\n", pkgid);
+		free(info->script_path);
+		return false;
+    }
+
+	// construct get_pkg_attrs script cmd and invoke it
+	size_t cmd_len = strlen(PKG_INFO_CMD) + script_path_len + 3;
+	char* cmd = malloc(cmd_len + 1);
+	snprintf(cmd, cmd_len + 1, "%s '%s'", PKG_INFO_CMD, info->script_path);
+	FILE* getinfo_fp = popen(cmd, "r");
+	free(cmd);
+	if (getinfo_fp == NULL) {
+        perror("failed to popen get_pkg_attrs");
+		exit(1); // fatal error
+    }
+
+	// go through each NULL delimited section of the output (attributes)
+	size_t n = 0;
+	char* line = NULL;
+	ssize_t read;
+	while ((read = getdelim(&line, &n, '\0', getinfo_fp)) != -1) {
+		// read in property based on first attribute type character
+		char  atype  = line[0];
+		char* avalue = line+1;
+		switch (atype) {
+			case 'i':
+				// id
+				info->id = strdup(avalue);
+				break;
+			case 'n':
+				// name
+				info->name = strdup(avalue);
+				break;
+			case 'd':
+				// description
+				info->desc = strdup(avalue);
+				break;
+		}
+    }
+	free(line);
+
+	// close the get_pkg_attrs process
+	int close_err = pclose(getinfo_fp);
+	if (close_err == -1) {
+        perror("failed to pclose get_pkg_attrs");
+		exit(1); // fatal error
+	} else if (close_err != 0) {
+		fprintf(stderr, "failed to execute get_pkg_attrs: %d\n", close_err);
+		exit(1); // fatal error
+	}
+
+	return true;
+}