gawk

commit b009d1b81e1ed073de76b11d6b47ed8fcdc4ca0d
parent 8cae8e4f31cd38b441bc583c8038d212be7b5db8
Author: Jacob R. Edwards <jacobouno@protonmail.com>
Date:   Sun, 20 Dec 2020 22:46:44 -0800

Add file downloading command `f`

Diffstat:
M
main.c
 | 
122
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++-----------

1 file changed, 106 insertions(+), 16 deletions(-)
diff --git a/main.c b/main.c
@@ -22,6 +22,7 @@
 #include <ctype.h>
 #include <err.h>
 #include <errno.h>
+#include <libgen.h>
 #include <limits.h>
 #include <netdb.h>
 #include <poll.h>
@@ -32,10 +33,13 @@
 
 #define LEN(X) (sizeof(X) / sizeof(*X))
 
+#define FETCH_MESSAGE
 #define BUFSIZE		4096
 #define ARGV_MAX	16
 #define ARG_SEP		":\t "
 
+enum gphitem { GI_INFO, GI_PATH, GI_HOST, GI_PORT, GI_NULL };
+
 static int timeout = 5 * 1000;
 static char *gphfmt[] = { "gophmt", NULL };
 
@@ -255,7 +259,7 @@ gphsend(int sock, const char *request)
 }
 
 int
-gphcache(const char *cache, const char *host, const char *path, const char *port)
+selwrite(const char *host, const char *port, const char *selector, const char *file)
 {
 	int sock;
 
@@ -263,8 +267,8 @@ gphcache(const char *cache, const char *host, const char *path, const char *port
 	if (sock == -1)
 		return 1;
 
-	if (gphsend(sock, path) != 0 ||
-	    fetch(sock, cache) != 0) {
+	if (gphsend(sock, selector) != 0 ||
+	    fetch(sock, file) != 0) {
 		close(sock);
 		return 1;
 	}
@@ -283,7 +287,7 @@ pipedup(int old, int new, int fildes[2])
 }
 
 int
-efmt(int (*putter)(const char *, int, const char **), const char *path, int argc, const char **argv)
+exfmt(int (*putter)(const char *, int, const char **), const char *path, int argc, const char **argv)
 {
 	int fds[2];
 	int i;
@@ -354,25 +358,37 @@ cgoto(int argc, const char **argv, int depth, const char *tmpdir, const char *ho
 }
 
 int
-cback(int argc, const char **argv)
+strtorange(unsigned int min, int max, const char *s)
 {
+	unsigned long n;
 	char *ep;
-	unsigned long back;
+
+	n = strtoul(s, &ep, 0);
+	if (*s == '\0' || *ep != '\0') {
+		warnc(EINVAL, "not a number '%s'", s);
+		return -1;
+	} else if ((errno == ERANGE && n == ULONG_MAX) ||
+		    n < min || n > max) {
+		warnc(ERANGE, "'%s'", s);
+		return -1;
+	}
+
+	return n;
+}
+
+int
+cback(int argc, const char **argv)
+{
+	int back;
 
 	wunused(1, argc, argv);
 
 	if (argc == 0)
 		return 1;	/* back `1`, not an error */
 
-	back = strtoul(argv[0], &ep, 0);
-	if (*ep != '\0' || (back == 0 && errno == EINVAL)) {
-		warnc(EINVAL, "'%s'", argv[0]);
+	back = strtorange(1, INT_MAX, argv[0]);
+	if (back < 0)
 		return 0;
-	} else if (back > INT_MAX) {
-		warnc(ERANGE, "'%s'", argv[0]);
-		return 0;
-	}
-
 	return back;
 }
 
@@ -411,6 +427,77 @@ cmatch(const char *path, int argc, const char **argv)
 	return 0;
 }
 
+/* argv[0] is the line index (starting from 0) of the file to
+ * download. If present argv[1] is the location to write the file
+ * to, otherwise it is written to the basename(3) of it's selector
+ * string.
+*/
+int
+cfetch(int argc, const char **argv, const char *cache, const char *host, const char *port)
+{
+	FILE *fp;
+	char *fields[GI_NULL + 1];
+	char *line;
+	const char *output;
+	int error;
+	int i, index;
+	size_t size;
+
+	if (argc == 0) {
+		warn("No index given");
+		return 1;
+	}
+	wunused(2, argc, argv);
+
+	index = strtorange(0, INT_MAX, argv[0]);
+	if (index < 0)
+		return 0;
+	if (argv[1])
+		output = argv[1];
+	else	output = NULL;
+
+	fp = wfopen(cache, "r");
+	if (fp == NULL)
+		return 1;
+
+	error = 0;
+	line = NULL;
+	size = 0;
+	for (i = 0; getline(&line, &size, fp) != -1; ++i) {
+		if (i != index) 
+			continue;
+		if (argsplit(fields, LEN(fields), line, "\t\r\n") != LEN(fields) - 1) {
+			warnx("Not a valid gopher item.");
+			++error;
+			goto cleanup;
+		}
+		if (output == NULL)
+			if ((output = basename(fields[GI_PATH])) == NULL) {
+				warn("unable to get basename '%s'", fields[GI_PATH]);
+				++error;
+				goto cleanup;
+			}
+		if (selwrite(fields[GI_HOST], fields[GI_PORT], fields[GI_PATH], output) != 0)
+			++error;
+		goto cleanup;
+	}
+
+cleanup:
+#ifdef FETCH_MESSAGE
+	if (!error)
+		warnx("'%s/%s' written to '%s'", fields[GI_HOST], fields[GI_PATH], output);
+#endif
+	free(line);
+	if (wfclose(fp) || error)
+		return 1;
+	if (i < index) {
+		warnx("%d: Out of range.", i);
+		return 1;
+	}
+
+	return 0;
+}
+
 int
 execute(int command, int argc, const char **argv, int depth, const char *cache,
     const char *tmpdir, const char *host, const char *path, const char *port)
@@ -420,7 +507,10 @@ execute(int command, int argc, const char **argv, int depth, const char *cache,
 		wunused(0, argc, argv);
 		return depth;
 	case 'p':
-		efmt(cmatch, cache, argc, argv);
+		exfmt(cmatch, cache, argc, argv);
+		return 0;
+	case 'f':
+		cfetch(argc, argv, cache, host, port);
 		return 0;
 	case 'b':
 		return cback(argc, argv);
@@ -451,7 +541,7 @@ gawk(int depth, const char *tmpdir, const char *host, const char *path, const ch
 		unlinkit = 0;
 	else {
 		unlinkit = 1;
-		if (gphcache(cache, host, path, port) == 1)
+		if (selwrite(host, port, path, cache) == 1)
 			return 0;	/* let the user handle it */
 	}