Add support for snapshots

Make a link from the commit viewer to a snapshot of the corresponding tree.

Currently only zip-format is supported.

Signed-off-by: Lars Hjemli <hjemli@gmail.com>

8 files changed, 153 insertions, 8 deletions

diff --git a/Makefile b/Makefile
index d826f97..b1c3a4e 100644
--- a/Makefile
+++ b/Makefile
@@ -6,7 +6,8 @@ gitsrc = ../git
 CACHE_ROOT = /var/cache/cgit
 EXTLIBS = $(gitsrc)/libgit.a $(gitsrc)/xdiff/lib.a -lz -lcrypto
 OBJECTS = shared.o cache.o parsing.o html.o ui-shared.o ui-repolist.o \
-	ui-summary.o ui-log.o ui-view.c ui-tree.c ui-commit.c ui-diff.o
+	ui-summary.o ui-log.o ui-view.c ui-tree.c ui-commit.c ui-diff.o \
+	ui-snapshot.o
 
 CFLAGS += -Wall
 
diff --git a/cgit.c b/cgit.c
index 0fa203c..2795ecc 100644
--- a/cgit.c
+++ b/cgit.c
@@ -78,6 +78,13 @@ static void cgit_print_repo_page(struct cacheitem *item)
 	title = fmt("%s - %s", cgit_repo->name, cgit_repo->desc);
 	show_search = 0;
 	setenv("GIT_DIR", cgit_repo->path, 1);
+
+	if (cgit_query_page && !strcmp(cgit_query_page, "snapshot")) {
+		cgit_print_snapshot(item, cgit_query_sha1, "zip", 
+				    cgit_repo->url, cgit_query_name);
+		return;
+	}
+
 	if (cgit_query_page && !strcmp(cgit_query_page, "log"))
 		show_search = 1;
 	cgit_print_docstart(title, item);
@@ -85,7 +92,8 @@ static void cgit_print_repo_page(struct cacheitem *item)
 	if (!cgit_query_page) {
 		cgit_print_summary();
 	} else if (!strcmp(cgit_query_page, "log")) {
-		cgit_print_log(cgit_query_head, cgit_query_ofs, 100, cgit_query_search);
+		cgit_print_log(cgit_query_head, cgit_query_ofs, 100, 
+			       cgit_query_search);
 	} else if (!strcmp(cgit_query_page, "tree")) {
 		cgit_print_tree(cgit_query_sha1, cgit_query_path);
 	} else if (!strcmp(cgit_query_page, "commit")) {
@@ -94,21 +102,39 @@ static void cgit_print_repo_page(struct cacheitem *item)
 		cgit_print_view(cgit_query_sha1);
 	} else if (!strcmp(cgit_query_page, "diff")) {
 		cgit_print_diff(cgit_query_sha1, cgit_query_sha2);
+	} else {
+		cgit_print_error("Invalid request");
 	}
 	cgit_print_docend();
 }
 
-static void cgit_fill_cache(struct cacheitem *item)
+static void cgit_fill_cache(struct cacheitem *item, int use_cache)
 {
 	static char buf[PATH_MAX];
+	int stdout2;
 
 	getcwd(buf, sizeof(buf));
-	htmlfd = item->fd;
 	item->st.st_mtime = time(NULL);
+
+	if (use_cache) {
+		stdout2 = chk_positive(dup(STDOUT_FILENO), 
+				       "Preserving STDOUT");
+		chk_zero(close(STDOUT_FILENO), "Closing STDOUT");
+		chk_positive(dup2(item->fd, STDOUT_FILENO), "Dup2(cachefile)");
+	}
+
 	if (cgit_query_repo)
 		cgit_print_repo_page(item);
 	else
 		cgit_print_repolist(item);
+
+	if (use_cache) {
+		chk_zero(close(STDOUT_FILENO), "Close redirected STDOUT");
+		chk_positive(dup2(stdout2, STDOUT_FILENO), 
+			     "Restoring original STDOUT");
+		chk_zero(close(stdout2), "Closing temporary STDOUT");
+	}
+
 	chdir(buf);
 }
 
@@ -127,14 +153,14 @@ static void cgit_check_cache(struct cacheitem *item)
 			goto top;
 		}
 		if (!cache_exist(item)) {
-			cgit_fill_cache(item);
+			cgit_fill_cache(item, 1);
 			cache_unlock(item);
 		} else {
 			cache_cancel_lock(item);
 		}
 	} else if (cache_expired(item) && cache_lock(item)) {
 		if (cache_expired(item)) {
-			cgit_fill_cache(item);
+			cgit_fill_cache(item, 1);
 			cache_unlock(item);
 		} else {
 			cache_cancel_lock(item);
@@ -209,8 +235,7 @@ int main(int argc, const char **argv)
 	if (!cgit_prepare_cache(&item))
 		return 0;
 	if (cgit_nocache) {
-		item.fd = STDOUT_FILENO;
-		cgit_fill_cache(&item);
+		cgit_fill_cache(&item, 0);
 	} else {
 		cgit_check_cache(&item);
 		cgit_print_cache(&item);
diff --git a/cgit.h b/cgit.h
index 2a3cd5a..03c2fdb 100644
--- a/cgit.h
+++ b/cgit.h
@@ -85,6 +85,7 @@ extern char *cgit_query_head;
 extern char *cgit_query_sha1;
 extern char *cgit_query_sha2;
 extern char *cgit_query_path;
+extern char *cgit_query_name;
 extern int   cgit_query_ofs;
 
 extern int htmlfd;
@@ -93,6 +94,9 @@ extern void cgit_global_config_cb(const char *name, const char *value);
 extern void cgit_repo_config_cb(const char *name, const char *value);
 extern void cgit_querystring_cb(const char *name, const char *value);
 
+extern int chk_zero(int result, char *msg);
+extern int chk_positive(int result, char *msg);
+
 extern int hextoint(char c);
 
 extern void *cgit_free_commitinfo(struct commitinfo *info);
@@ -130,6 +134,9 @@ extern void cgit_print_date(unsigned long secs);
 extern void cgit_print_docstart(char *title, struct cacheitem *item);
 extern void cgit_print_docend();
 extern void cgit_print_pageheader(char *title, int show_search);
+extern void cgit_print_snapshot_start(const char *mimetype, 
+				      const char *filename, 
+				      struct cacheitem *item);
 
 extern void cgit_print_repolist(struct cacheitem *item);
 extern void cgit_print_summary();
@@ -138,5 +145,8 @@ extern void cgit_print_view(const char *hex);
 extern void cgit_print_tree(const char *hex, char *path);
 extern void cgit_print_commit(const char *hex);
 extern void cgit_print_diff(const char *old_hex, const char *new_hex);
+extern void cgit_print_snapshot(struct cacheitem *item, const char *hex, 
+				const char *format, const char *prefix,
+				const char *filename);
 
 #endif /* CGIT_H */
diff --git a/git.h b/git.h
index eca48d5..a1d1c4b 100644
--- a/git.h
+++ b/git.h
@@ -669,4 +669,31 @@ int log_tree_commit(struct rev_info *, struct commit *);
 
 
 
+/* from git:archive.h */
+
+struct archiver_args {
+	const char *base;
+	struct tree *tree;
+	const unsigned char *commit_sha1;
+	time_t time;
+	const char **pathspec;
+	unsigned int verbose : 1;
+	void *extra;
+};
+
+typedef int (*write_archive_fn_t)(struct archiver_args *);
+
+typedef void *(*parse_extra_args_fn_t)(int argc, const char **argv);
+
+struct archiver {
+	const char *name;
+	struct archiver_args args;
+	write_archive_fn_t write_archive;
+	parse_extra_args_fn_t parse_extra;
+};
+
+extern int write_tar_archive(struct archiver_args *);
+extern int write_zip_archive(struct archiver_args *);
+extern void *parse_extra_zip_args(int argc, const char **argv);
+
 #endif /* GIT_H */
diff --git a/shared.c b/shared.c
index 6fd70a8..5757d0c 100644
--- a/shared.c
+++ b/shared.c
@@ -44,10 +44,25 @@ char *cgit_query_search = NULL;
 char *cgit_query_sha1   = NULL;
 char *cgit_query_sha2   = NULL;
 char *cgit_query_path   = NULL;
+char *cgit_query_name   = NULL;
 int   cgit_query_ofs    = 0;
 
 int htmlfd = 0;
 
+int chk_zero(int result, char *msg)
+{
+	if (result != 0)
+		die("%s: %s", msg, strerror(errno));
+	return result;
+}
+
+int chk_positive(int result, char *msg)
+{
+	if (result <= 0)
+		die("%s: %s", msg, strerror(errno));
+	return result;
+}
+
 struct repoinfo *add_repo(const char *url)
 {
 	struct repoinfo *ret;
@@ -140,6 +155,8 @@ void cgit_querystring_cb(const char *name, const char *value)
 		cgit_query_ofs = atoi(value);
 	} else if (!strcmp(name, "path")) {
 		cgit_query_path = xstrdup(value);
+	} else if (!strcmp(name, "name")) {
+		cgit_query_name = xstrdup(value);
 	}
 }
 
diff --git a/ui-commit.c b/ui-commit.c
index 73fa104..de3f2cf 100644
--- a/ui-commit.c
+++ b/ui-commit.c
@@ -128,6 +128,7 @@ void cgit_print_commit(const char *hex)
 	struct commit_list *p;
 	unsigned char sha1[20];
 	char *query;
+	char *filename;
 
 	if (get_sha1(hex, sha1)) {
 		cgit_print_error(fmt("Bad object id: %s", hex));
@@ -168,6 +169,12 @@ void cgit_print_commit(const char *hex)
 		htmlf("'>%s</a></td></tr>\n", 
 		      sha1_to_hex(p->item->object.sha1));
 	}
+	htmlf("<tr><th>download</th><td colspan='2' class='sha1'><a href='");
+	filename = fmt("%s-%s.zip", cgit_query_repo, hex);
+	html_attr(cgit_pageurl(cgit_query_repo, "snapshot", 
+			       fmt("id=%s&name=%s", hex, filename)));
+	htmlf("'>%s</a></td></tr>", filename);
+	
 	html("</table>\n");
 	html("<div class='commit-subject'>");
 	html_txt(info->subject);
diff --git a/ui-shared.c b/ui-shared.c
index 3322561..172499c 100644
--- a/ui-shared.c
+++ b/ui-shared.c
@@ -144,3 +144,14 @@ void cgit_print_pageheader(char *title, int show_search)
 		html("</a>");
 	html("</td></tr><tr><td id='content'>");
 }
+
+void cgit_print_snapshot_start(const char *mimetype, const char *filename, 
+			       struct cacheitem *item)
+{
+	htmlf("Content-Type: %s\n", mimetype);
+	htmlf("Content-Disposition: inline; filename=\"%s\"\n", filename);
+	htmlf("Last-Modified: %s\n", http_date(item->st.st_mtime));
+	htmlf("Expires: %s\n", http_date(item->st.st_mtime +
+					 ttl_seconds(item->ttl)));
+	html("\n");
+}
diff --git a/ui-snapshot.c b/ui-snapshot.c
new file mode 100644
index 0000000..2257d6b
--- /dev/null
+++ b/ui-snapshot.c
@@ -0,0 +1,47 @@
+/* ui-snapshot.c: generate snapshot of a commit
+ *
+ * Copyright (C) 2006 Lars Hjemli
+ *
+ * Licensed under GNU General Public License v2
+ *   (see COPYING for full license text)
+ */
+
+#include "cgit.h"
+
+static void cgit_print_zip(struct cacheitem *item, const char *hex, 
+			   const char *prefix, const char *filename)
+{
+	struct archiver_args args;
+	struct commit *commit;
+	unsigned char sha1[20];
+
+	if (get_sha1(hex, sha1)) {
+		cgit_print_error(fmt("Bad object id: %s", hex));
+		return;
+	}
+	commit = lookup_commit_reference(sha1);
+
+	if (!commit) {
+		cgit_print_error(fmt("Not a commit reference: %s", hex));
+		return;
+	}
+
+	memset(&args, 0, sizeof(args));
+	args.base = fmt("%s/", prefix);
+	args.tree = commit->tree;
+	
+	cgit_print_snapshot_start("application/x-zip", filename, item);
+	write_zip_archive(&args);
+}
+
+
+void cgit_print_snapshot(struct cacheitem *item, const char *hex, 
+			 const char *format, const char *prefix,
+			 const char *filename)
+{
+	if (!strcmp(format, "zip"))
+		cgit_print_zip(item, hex, prefix, filename);
+	else
+		cgit_print_error(fmt("Unsupported snapshot format: %s", 
+				     format));
+}