torrentd

commit 7d546dd306c2f101d6cc41d40db3dc1128c22df2
parent e33b18d011bf61e0eafad98edd381a9544f91a6d
Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date:   Fri, 18 Dec 2015 21:27:03 +0100

multi-file mode and other improvements

- unify single-file and multi-file mode.
- use "name" as suggested directory name in multi-file mode
  in single-file mode it is always "".
- calculate length of pieces based on total data size.
- do some additional type checks.

Diffstat:
M
sbtd.h
 | 
8
+++++++-
M
torrent.c
 | 
94
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++----------

2 files changed, 90 insertions(+), 12 deletions(-)
diff --git a/sbtd.h b/sbtd.h
@@ -25,6 +25,11 @@ struct ben {
 	struct ben *next;
 };
 
+struct file {
+	size_t len;
+	char *path;
+};
+
 struct torrent {
 	char *buf;
 	size_t buflen;
@@ -33,8 +38,9 @@ struct torrent {
 	struct ben *pieces;
 	char *announce;
 	char *filename;
+	struct file *files;
+	size_t nfiles;
 	uint8_t infohash[20];
-	long long length;
 	long long piecelen;
 	long long npieces;
 	uint32_t *piecebm;
diff --git a/torrent.c b/torrent.c
@@ -36,12 +36,21 @@ dumptorrent(struct torrent *t)
 	uint8_t md[20];
 	char hex[41];
 	long long i;
+	size_t n;
 
 	printf("announce: %s\n", t->announce);
-	printf("filename: %s\n", t->filename);
+
+	if (t->filename[0])
+		printf("directory: %s\n", t->filename);
+	if (t->nfiles)
+		printf("files (%zu):\n", t->nfiles);
+	for (n = 0; n < t->nfiles; n++) {
+		printf("\tpath: %s, length: %zu\n",
+		       t->files[n].path, t->files[n].len);
+	}
+
 	bin2hex(t->infohash, hex, 20);
 	printf("infohash: %s\n", hex);
-	printf("length: %lld\n", t->length);
 	printf("piecelen: %lld\n", t->piecelen);
 	printf("npieces: %lld\n", t->npieces);
 
@@ -56,6 +65,9 @@ struct torrent *
 loadtorrent(char *f)
 {
 	struct torrent *t;
+	struct ben *files, *file;
+	struct ben *length, *path, *tmp;
+	size_t n, pathlen, totallen = 0;
 
 	t = emalloc(sizeof(*t));
 	if (readfile(f, &t->buf, &t->buflen) < 0) {
@@ -95,14 +107,70 @@ loadtorrent(char *f)
 	}
 	t->filename = bstr2str(dlookstr(t->info, "name"));
 
-	if (!dlookstr(t->info, "length")) {
-		warnx("no length field in %s", f);
-		goto err2;
-	}
-	t->length = dlookstr(t->info, "length")->i;
-	if (t->length <= 0) {
-		warnx("length is <= 0 in %s", f);
-		goto err2;
+	/* multi-file mode or single file ? */
+	if ((files = dlookstr(t->info, "files"))) {
+		if (files->type != 'l') {
+			warnx("invalid: \"files\" not a list");
+			goto err2;
+		}
+		t->nfiles = files->len;
+		t->files = ecalloc(files->len, sizeof(struct file));
+
+		for (file = files, n = 0; file; file = file->next, n++) {
+			if (!(length = dlookstr(file->v, "length"))) {
+				warnx("no length field in %s", f);
+				goto err3;
+			}
+			if (length->type != 'i') {
+				warnx("length must be of type integer");
+				goto err3;
+			}
+			if (length->i < 0) {
+				warnx("length is < 0 in %s", f);
+				goto err3;
+			}
+			totallen += (size_t)length->i;
+			t->files[n].len = (size_t)length->i;
+
+			if (!(path = dlookstr(file->v, "path")))
+				break;
+			if (path->type != 'l')
+				warnx("path must be of type list");
+
+			/* check path list and count path buffer size */
+			for (tmp = path, pathlen = 0; tmp; tmp = tmp->next) {
+				if (tmp->v->type != 's') {
+					warnx("path item must be of type string");
+					goto err2;
+				}
+				pathlen += tmp->v->len + 1;
+			}
+			t->files[n].path = ecalloc(1, pathlen);
+			for (tmp = path; tmp; tmp = tmp->next) {
+				strlcat(t->files[n].path, tmp->v->s, pathlen);
+				if (tmp != path && tmp->next)
+					strlcat(t->files[n].path, "/", pathlen);
+			}
+		}
+	} else {
+		if (!(length = dlookstr(t->info, "length"))) {
+			warnx("no length field in %s", f);
+			goto err2;
+		}
+		if (length->type != 'i') {
+			warnx("length must be of type integer");
+			goto err2;
+		}
+		if (length->i < 0) {
+			warnx("length is < 0 in %s", f);
+			goto err2;
+		}
+		t->nfiles = n = 1;
+		t->files = ecalloc(1, sizeof(struct file));
+		t->files[0].len = length->i;
+		t->files[0].path = strdup(t->filename);
+		t->filename = "";
+		totallen = (size_t)length->i;
 	}
 
 	if (!dlookstr(t->info, "piece length")) {
@@ -115,12 +183,16 @@ loadtorrent(char *f)
 		goto err2;
 	}
 
-	t->npieces = (t->length + t->piecelen - 1) / t->piecelen;
+	t->npieces = (totallen + t->piecelen - 1) / t->piecelen;
 	t->piecebm = newbit(t->npieces);
 
 	calcinfohash(t);
 
 	return t;
+err3:
+	while (n--)
+		free(t->files[n].path);
+	free(t->files);
 err2:
 	bfree(t->ben);
 err1: