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
@@ -1,33 +1,34 @@
 CGIT_VERSION = 0.2
 
 prefix = /var/www/htdocs/cgit
 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
 
 ifdef DEBUG
         CFLAGS += -g
 endif
 
 all: cgit
 
 install: all clean-cache
         mkdir -p $(prefix)
         install cgit $(prefix)/cgit.cgi
         install cgit.css $(prefix)/cgit.css
 
 cgit: cgit.c cgit.h git.h $(OBJECTS) $(gitsrc)/libgit.a
         $(CC) $(CFLAGS) -DCGIT_VERSION='"$(CGIT_VERSION)"' cgit.c -o cgit \
                 $(OBJECTS) $(EXTLIBS)
 
 $(OBJECTS): cgit.h git.h
 
 ui-diff.o: xdiff.h
 
 $(gitsrc)/libgit.a:
         $(MAKE) -C $(gitsrc)
diff --git a/cgit.c b/cgit.c
index 0fa203c..2795ecc 100644
--- a/cgit.c
+++ b/cgit.c
@@ -57,105 +57,131 @@ static int cgit_prepare_cache(struct cacheitem *item)
                 else
                         item->ttl = cgit_cache_repo_ttl;
         }
         return 1;
 }
 
 static void cgit_print_repo_page(struct cacheitem *item)
 {
         char *title;
         int show_search;
 
         if (chdir(cgit_repo->path)) {
                 title = fmt("%s - %s", cgit_root_title, "Bad request");
                 cgit_print_docstart(title, item);
                 cgit_print_pageheader(title, 0);
                 cgit_print_error(fmt("Unable to scan repository: %s",
                                      strerror(errno)));
                 cgit_print_docend();
                 return;
         }
 
         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);
         cgit_print_pageheader(title, show_search);
         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")) {
                 cgit_print_commit(cgit_query_sha1);
         } else if (!strcmp(cgit_query_page, "view")) {
                 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);
 }
 
 static void cgit_check_cache(struct cacheitem *item)
 {
         int i = 0;
 
  top:
         if (++i > cgit_max_lock_attempts) {
                 die("cgit_refresh_cache: unable to lock %s: %s",
                     item->name, strerror(errno));
         }
         if (!cache_exist(item)) {
                 if (!cache_lock(item)) {
                         sleep(1);
                         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);
                 }
         }
 }
 
 static void cgit_print_cache(struct cacheitem *item)
 {
         static char buf[4096];
         ssize_t i;
 
         int fd = open(item->name, O_RDONLY);
         if (fd<0)
                 die("Unable to open cached file %s", item->name);
 
         while((i=read(fd, buf, sizeof(buf))) > 0)
                 write(STDOUT_FILENO, buf, i);
 
         close(fd);
 }
 
 static void cgit_parse_args(int argc, const char **argv)
 {
@@ -188,32 +214,31 @@ static void cgit_parse_args(int argc, const char **argv)
                 if (!strncmp(argv[i], "--ofs=", 6)) {
                         cgit_query_ofs = atoi(argv[i]+6);
                 }
         }
 }
 
 int main(int argc, const char **argv)
 {
         struct cacheitem item;
 
         htmlfd = STDOUT_FILENO;
         item.st.st_mtime = time(NULL);
         cgit_repolist.length = 0;
         cgit_repolist.count = 0;
         cgit_repolist.repos = NULL;
 
         cgit_read_config("/etc/cgitrc", cgit_global_config_cb);
         if (getenv("QUERY_STRING"))
                 cgit_querystring = xstrdup(getenv("QUERY_STRING"));
         cgit_parse_args(argc, argv);
         cgit_parse_query(cgit_querystring, cgit_querystring_cb);
         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);
         }
         return 0;
 }
diff --git a/cgit.h b/cgit.h
index 2a3cd5a..03c2fdb 100644
--- a/cgit.h
+++ b/cgit.h
@@ -64,79 +64,89 @@ extern int cgit_nocache;
 extern int cgit_max_lock_attempts;
 extern int cgit_cache_root_ttl;
 extern int cgit_cache_repo_ttl;
 extern int cgit_cache_dynamic_ttl;
 extern int cgit_cache_static_ttl;
 extern int cgit_cache_max_create_time;
 
 extern int cgit_max_msg_len;
 
 extern char *cgit_repo_name;
 extern char *cgit_repo_desc;
 extern char *cgit_repo_owner;
 
 extern int cgit_query_has_symref;
 extern int cgit_query_has_sha1;
 
 extern char *cgit_querystring;
 extern char *cgit_query_repo;
 extern char *cgit_query_page;
 extern char *cgit_query_search;
 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;
 
 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);
 
 extern char *fmt(const char *format,...);
 
 extern void html(const char *txt);
 extern void htmlf(const char *format,...);
 extern void html_txt(char *txt);
 extern void html_ntxt(int len, char *txt);
 extern void html_attr(char *txt);
 extern void html_hidden(char *name, char *value);
 extern void html_link_open(char *url, char *title, char *class);
 extern void html_link_close(void);
 extern void html_filemode(unsigned short mode);
 
 extern int cgit_read_config(const char *filename, configfn fn);
 extern int cgit_parse_query(char *txt, configfn fn);
 extern struct commitinfo *cgit_parse_commit(struct commit *commit);
 extern struct taginfo *cgit_parse_tag(struct tag *tag);
 
 extern char *cache_safe_filename(const char *unsafe);
 extern int cache_lock(struct cacheitem *item);
 extern int cache_unlock(struct cacheitem *item);
 extern int cache_cancel_lock(struct cacheitem *item);
 extern int cache_exist(struct cacheitem *item);
 extern int cache_expired(struct cacheitem *item);
 
 extern char *cgit_repourl(const char *reponame);
 extern char *cgit_pageurl(const char *reponame, const char *pagename, 
                           const char *query);
 
 extern void cgit_print_error(char *msg);
 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();
 extern void cgit_print_log(const char *tip, int ofs, int cnt, char *grep);
 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
@@ -648,25 +648,52 @@ struct rev_info {
         /* diff info for patches and for paths limiting */
         struct diff_options diffopt;
         struct diff_options pruning;
 
         topo_sort_set_fn_t topo_setter;
         topo_sort_get_fn_t topo_getter;
 };
 
 
 extern void init_revisions(struct rev_info *revs, const char *prefix);
 extern int setup_revisions(int argc, const char **argv, struct rev_info *revs, const char *def);
 extern int handle_revision_arg(const char *arg, struct rev_info *revs,int flags,int cant_be_filename);
 
 extern void prepare_revision_walk(struct rev_info *revs);
 extern struct commit *get_revision(struct rev_info *revs);
 
 
 
 /* from git:log-tree.h */
 
 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
@@ -23,52 +23,67 @@ int cgit_nocache               =  0;
 int cgit_max_lock_attempts     =  5;
 int cgit_cache_root_ttl        =  5;
 int cgit_cache_repo_ttl        =  5;
 int cgit_cache_dynamic_ttl     =  5;
 int cgit_cache_static_ttl      = -1;
 int cgit_cache_max_create_time =  5;
 
 int cgit_max_msg_len = 60;
 
 char *cgit_repo_name    = NULL;
 char *cgit_repo_desc    = NULL;
 char *cgit_repo_owner   = NULL;
 
 int cgit_query_has_symref = 0;
 int cgit_query_has_sha1   = 0;
 
 char *cgit_querystring  = NULL;
 char *cgit_query_repo   = NULL;
 char *cgit_query_page   = NULL;
 char *cgit_query_head   = NULL;
 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;
 
         if (++cgit_repolist.count > cgit_repolist.length) {
                 if (cgit_repolist.length == 0)
                         cgit_repolist.length = 8;
                 else
                         cgit_repolist.length *= 2;
                 cgit_repolist.repos = xrealloc(cgit_repolist.repos, 
                                                cgit_repolist.length * 
                                                sizeof(struct repoinfo));
         }
 
         ret = &cgit_repolist.repos[cgit_repolist.count-1];
         ret->url = xstrdup(url);
         ret->name = ret->url;
         ret->path = NULL;
         ret->desc = NULL;
         ret->owner = NULL;
         return ret;
 }
 
 void cgit_global_config_cb(const char *name, const char *value)
@@ -119,48 +134,50 @@ void cgit_repo_config_cb(const char *name, const char *value)
                 cgit_repo_owner = xstrdup(value);
 }
 
 void cgit_querystring_cb(const char *name, const char *value)
 {
         if (!strcmp(name,"r")) {
                 cgit_query_repo = xstrdup(value);
         } else if (!strcmp(name, "p")) {
                 cgit_query_page = xstrdup(value);
         } else if (!strcmp(name, "q")) {
                 cgit_query_search = xstrdup(value);
         } else if (!strcmp(name, "h")) {
                 cgit_query_head = xstrdup(value);
                 cgit_query_has_symref = 1;
         } else if (!strcmp(name, "id")) {
                 cgit_query_sha1 = xstrdup(value);
                 cgit_query_has_sha1 = 1;
         } else if (!strcmp(name, "id2")) {
                 cgit_query_sha2 = xstrdup(value);
                 cgit_query_has_sha1 = 1;
         } else if (!strcmp(name, "ofs")) {
                 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);
         }
 }
 
 void *cgit_free_commitinfo(struct commitinfo *info)
 {
         free(info->author);
         free(info->author_email);
         free(info->committer);
         free(info->committer_email);
         free(info->subject);
         free(info);
         return NULL;
 }
 
 int hextoint(char c)
 {
         if (c >= 'a' && c <= 'f')
                 return 10 + c - 'a';
         else if (c >= 'A' && c <= 'F')
                 return 10 + c - 'A';
         else if (c >= '0' && c <= '9')
                 return c - '0';
         else
                 return -1;
diff --git a/ui-commit.c b/ui-commit.c
index 73fa104..de3f2cf 100644
--- a/ui-commit.c
+++ b/ui-commit.c
@@ -107,79 +107,86 @@ void cgit_diffstat(struct commit *commit)
         opt.output_format = DIFF_FORMAT_CALLBACK;
         opt.detect_rename = 1;
         opt.recursive = 1;
         opt.format_callback = diff_format_cb;
         diff_setup_done(&opt);
         
         if (commit->parents)
                 ret = diff_tree_sha1(commit->parents->item->object.sha1,
                                      commit->object.sha1,
                                      "", &opt);
         else
                 ret = diff_root_tree_sha1(commit->object.sha1, "", &opt);
 
         diffcore_std(&opt);
         diff_flush(&opt);
 }
 
 void cgit_print_commit(const char *hex)
 {
         struct commit *commit;
         struct commitinfo *info;
         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));
                 return;
         }
         commit = lookup_commit_reference(sha1);
         if (!commit) {
                 cgit_print_error(fmt("Bad commit reference: %s", hex));
                 return;
         }
         info = cgit_parse_commit(commit);
 
         html("<table class='commit-info'>\n");
         html("<tr><th>author</th><td>");
         html_txt(info->author);
         html(" ");
         html_txt(info->author_email);
         html("</td><td class='right'>");
         cgit_print_date(info->author_date);
         html("</td></tr>\n");
         html("<tr><th>committer</th><td>");
         html_txt(info->committer);
         html(" ");
         html_txt(info->committer_email);
         html("</td><td class='right'>");
         cgit_print_date(info->committer_date);
         html("</td></tr>\n");
         html("<tr><th>tree</th><td colspan='2' class='sha1'><a href='");
         query = fmt("id=%s", sha1_to_hex(commit->tree->object.sha1));
         html_attr(cgit_pageurl(cgit_query_repo, "tree", query));
         htmlf("'>%s</a></td></tr>\n", sha1_to_hex(commit->tree->object.sha1));
               for (p = commit->parents; p ; p = p->next) {
                 html("<tr><th>parent</th>"
                      "<td colspan='2' class='sha1'>"
                      "<a href='");
                 query = fmt("id=%s", sha1_to_hex(p->item->object.sha1));
                 html_attr(cgit_pageurl(cgit_query_repo, "commit", query));
                 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);
         html("</div>");
         html("<div class='commit-msg'>");
         html_txt(info->msg);
         html("</div>");
         html("<table class='diffstat'>");
         html("<tr><th colspan='3'>Affected files</tr>\n");
         cgit_diffstat(commit);
         htmlf("<tr><td colspan='3' class='summary'>"
               "%d file%s changed</td></tr>\n", files, files > 1 ? "s" : "");
         html("</table>");
         cgit_free_commitinfo(info);
 }
diff --git a/ui-shared.c b/ui-shared.c
index 3322561..172499c 100644
--- a/ui-shared.c
+++ b/ui-shared.c
@@ -123,24 +123,35 @@ void cgit_print_pageheader(char *title, int show_search)
                 html("'>");
                 if (!cgit_virtual_root) {
                         if (cgit_query_repo)
                                 html_hidden("r", cgit_query_repo);
                         if (cgit_query_page)
                                 html_hidden("p", cgit_query_page);
                 }
                 if (cgit_query_head)
                         html_hidden("h", cgit_query_head);
                 if (cgit_query_sha1)
                         html_hidden("id", cgit_query_sha1);
                 if (cgit_query_sha2)
                         html_hidden("id2", cgit_query_sha2);
                 html("<input type='text' name='q' value='");
                 html_attr(cgit_query_search);
                 html("'/></form>");
         }
         if (cgit_query_repo)
                 htmlf("<a href='%s'>", cgit_repourl(cgit_query_repo));
         html_txt(title);
         if (cgit_query_repo)
                 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
--- a/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));
+}