read package info into snag

1 files changed, 78 insertions, 3 deletions

diff --git a/snag/main.c b/snag/main.c
index 9eacf33..10a5f86 100644
--- a/snag/main.c
+++ b/snag/main.c
@@ -1,12 +1,17 @@
 #include <stdio.h>
 #include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 
-#define DESC_DIR "../snaggies"
+#define PKG_DB "../snaggies"
+#define PKG_INFO_CMD "./snagpkginfo.sh"
 
 typedef struct {
 	char* id;
 	char* name;
 	char* desc;
+	char* script_path;
 } package_info_t;
 
 void subcmd_install(char* pkgs[], size_t count);
@@ -25,9 +30,79 @@ void subcmd_install(char* pkgs[], size_t count) {
 	// install each package listed
 	for (int i = 0; i < count; ++i) {
 
-		char* package = pkgs[i];
-		printf("Installing '%s'\n", package);
+		char* pkgid = pkgs[i];
 
 		// load package description
+		package_info_t info;
+		if (load_package_info(&info, pkgid)) {
+			printf("Installing '%s'\n", info.name);
+		}
 	}
 }
+
+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;
+    }
+
+	// run getpkginfo script that outputs package attributes
+	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");
+	if (getinfo_fp == NULL) {
+        perror("failed to popen getpkginfo");
+		exit(1); // fatal error
+    }
+
+	// go through each NULL delimited section of the output
+	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 getpkginfo process
+	if (pclose(getinfo_fp) != 0) {
+        perror("failed to pclose getpkginfo");
+		exit(1); // fatal error
+	}
+
+	return true;
+}