gawk

commit e6092335feee193caeb1360be8a95c61756b2729
parent 9787d16a53436f6c7bfeb54b03dd2b695981fa70
Author: Jacob R. Edwards <jacobouno@protonmail.com>
Date:   Sat, 19 Dec 2020 14:12:13 -0800

Add caching

Add file caching although you still cannot display the content.

Diffstat:
M
main.c
 | 
123
++++++++++++++++++++++++++++++++++++++++++-------------------------------------

1 file changed, 66 insertions(+), 57 deletions(-)
diff --git a/main.c b/main.c
@@ -33,7 +33,16 @@
 #define ARGV_MAX	16
 #define ARG_SEP		":\t "
 
-static char *format_prog = "gophmt";	/* not released, costom formatter */
+FILE *
+wfopen(const char *path, const char *mode)
+{
+	FILE *fp;
+
+	fp = fopen(path, mode);
+	if (fp == NULL)
+		warn("unable to open '%s' ('%s')", path, mode);
+	return fp;
+}
 
 int
 resolve(struct addrinfo **ai, const char *host, const char *proto)
@@ -134,6 +143,22 @@ newpath(char *path, char *newpath)
 	}
 }
 
+void
+getcache(char *cache, const char *tmpdir, const char *host, const char *port, const char *path)
+{
+	int i;
+	char tmp[PATH_MAX];
+
+	for (i = 0; path[i] != '\0'; ++i) {
+		if (path[i] == '/')
+			tmp[i] = '-';
+		else
+			tmp[i] = path[i];
+	}
+	tmp[i] = '\0';
+	snprintf(cache, PATH_MAX, "%s/%s-%s-%s", tmpdir, host, port, tmp);
+}
+
 int
 argsplit(char **argv, int arg_max, char *s, const char *sep)
 {
@@ -151,81 +176,47 @@ argsplit(char **argv, int arg_max, char *s, const char *sep)
 	return argc;
 }
 
-/* NOTE: implement caching */
 int
-getgph(int sock, const char *path)
+fetch(int sock, const char *path)
 {
-	ssize_t bytes;
+	FILE *fp;
 	char buf[BUFSIZE];
+	ssize_t bytes;
+	int error;
 
-	/* NOTE: SIGPIPE is recieved */
-	if (send(sock, path, strlen(path), 0) == -1) {
-		warn("unable to send request");
+	fp = wfopen(path, "w+");
+	if (fp == NULL)
 		return 1;
-	}
 
 	while ((bytes = recv(sock, buf, sizeof(buf), 0)) > 0) {
-		if (fwrite(buf, 1, bytes, stdout) != bytes)
+		if (fwrite(buf, 1, bytes, fp) != bytes) {
+			fclose(fp);
 			return 1;
+		}
 	}
 
+	error = ferror(fp);
+	if (fclose(fp) || error)
+		return 1;
 	return 0;
 }
 
 int
-gawkat(int sock, const char *path)
+gawkat(const char *path)
 {
-	int status;
-	int fds[2];
-	char *argv[2];
-
-	if (pipe(fds) == -1) {
-		warn("unable to pipe");
-		return 1;
-	}
-
-	argv[0] = format_prog;
-	argv[1] = NULL;
-
-	switch (fork()) {
-	case -1:
-		warn("unable to fork");
-		return 1;
-	case 0:
-		if (dup2(fds[1], STDIN_FILENO) == -1) {
-			warn("unable to setup pipe");
-			_exit(1);
-		}
-		execvp(*argv, argv);
-		warn("execvp %s", *argv);
-		return 1;
-	default:
-		if (dup2(fds[0], STDOUT_FILENO) == -1) {
-			warn("unable to setup pipe");
-			status = 1;
-			break;
-		}
-		if ((status = getgph(sock, path)) == 0) {
-			wait(&status);
-			if (status)
-				warnx("child exited %d", status);
-		}
-	}
-
-	if (close(fds[0]) || close(fds[1]))
-		warn("unable to close pipe");
-
-	return status;
+	printf("gawking at %s\n", path);
+	return 0;
 }
 
 /* returns `<0` on error, if positive `n - 1` is
  * be returned to the caller. */
 int
-gawk(int sock, int depth, const char *host, const char *path, const char *port)
+gawk(int sock, int depth, const char *tmpdir, const char *host, const char *path, const char *port)
 {
 	char *argv[ARGV_MAX];
 	char inbuf[PATH_MAX + HOST_NAME_MAX + PROTO_MAX];	
 	char prompt[64];	/* you wouldn't want it longer anyway */
+	char cache[PATH_MAX];
 	const char *nreq[3];
 	int argc;
 	int closeit, done, newsock;
@@ -241,6 +232,16 @@ gawk(int sock, int depth, const char *host, const char *path, const char *port)
 			return -1;
 	}
 
+	if (send(sock, path, strlen(path), 0) == -1) {
+		warn("unable to send request");
+		return 1;
+	}
+
+	/* NOTE: could exist, test for it. */
+	getcache(cache, tmpdir, host, port, path);
+	if (fetch(sock, cache) != 0)
+		return 0;	/* just return to the previous, if any. */
+
 	snprintf(prompt, sizeof(prompt), "[%s] %s ", host, path);
 
 	done = 0;
@@ -261,9 +262,7 @@ gawk(int sock, int depth, const char *host, const char *path, const char *port)
 			done = depth;
 			break;
 		case 'p':	/* print */
-			puts("gawking");
-			/* NOTE: SIGPIPE on second call.
-			 * gawkat(sock, path); */
+			gawkat(path);
 			break;
 		case 'b':	/* back */
 			if (argc > 2)
@@ -301,7 +300,7 @@ gawk(int sock, int depth, const char *host, const char *path, const char *port)
 
 			if (!newsock)
 				newsock = sock;
-			done = gawk(newsock, depth, nreq[0], nreq[1], nreq[2]);
+			done = gawk(newsock, depth, tmpdir, nreq[0], nreq[1], nreq[2]);
 			break;
 		default:
 invalid_input:
@@ -309,6 +308,8 @@ invalid_input:
 		}
 	}
 
+	/* NOTE: cleanup cache files IF created in this function */
+
 	if (closeit && close(sock) == -1)
 		warn("unable to disconnect from '%s'", host);
 	if (ferror(stdin)) {
@@ -321,7 +322,15 @@ invalid_input:
 int
 main(int argc, char *argv[])
 {
-	gawk(-1, 0, "localhost", "/","gopher");
+	char t[64];
+	strcpy(t, "/tmp/gawk-XXXXXXXXXXX");
+	if (mkdtemp(t) == NULL)
+		err(1, "unable to create temp dir");
+
+	gawk(-1, 0, t, "localhost", "/","gopher");
+
+	if (rmdir(t) == -1)
+		err(1, "unable to remove temp dir");
 
 	return 0;
 }