Git.pm: Handle failed commands' output
[gitweb.git] / upload-pack.c
index 47560c9527b9c17db34f10e78d7c1f0d99b746e1..b18eb9ba0dbe8b5020aaaa698d98a4d1b76aa49c 100644 (file)
@@ -1,3 +1,6 @@
+#include <signal.h>
+#include <sys/wait.h>
+#include <sys/poll.h>
 #include "cache.h"
 #include "refs.h"
 #include "pkt-line.h"
@@ -18,6 +21,7 @@ static int use_thin_pack = 0;
 static unsigned char has_sha1[MAX_HAS][20];
 static unsigned char needs_sha1[MAX_NEEDS][20];
 static unsigned int timeout = 0;
+static int use_sideband = 0;
 
 static void reset_timeout(void)
 {
@@ -31,24 +35,68 @@ static int strip(char *line, int len)
        return len;
 }
 
+#define PACKET_MAX 1000
+static ssize_t send_client_data(int fd, const char *data, ssize_t sz)
+{
+       ssize_t ssz;
+       const char *p;
+
+       if (!data) {
+               if (!use_sideband)
+                       return 0;
+               packet_flush(1);
+       }
+
+       if (!use_sideband) {
+               if (fd == 3)
+                       /* emergency quit */
+                       fd = 2;
+               return safe_write(fd, data, sz);
+       }
+       p = data;
+       ssz = sz;
+       while (sz) {
+               unsigned n;
+               char hdr[5];
+
+               n = sz;
+               if (PACKET_MAX - 5 < n)
+                       n = PACKET_MAX - 5;
+               sprintf(hdr, "%04x", n + 5);
+               hdr[4] = fd;
+               safe_write(1, hdr, 5);
+               safe_write(1, p, n);
+               p += n;
+               sz -= n;
+       }
+       return ssz;
+}
+
 static void create_pack_file(void)
 {
-       int fd[2];
-       pid_t pid;
+       /* Pipes between rev-list to pack-objects, pack-objects to us
+        * and pack-objects error stream for progress bar.
+        */
+       int lp_pipe[2], pu_pipe[2], pe_pipe[2];
+       pid_t pid_rev_list, pid_pack_objects;
        int create_full_pack = (nr_our_refs == nr_needs && !nr_has);
+       char data[8193], progress[128];
+       char abort_msg[] = "aborting due to possible repository "
+               "corruption on the remote side.";
+       int buffered = -1;
 
-       if (pipe(fd) < 0)
+       if (pipe(lp_pipe) < 0)
                die("git-upload-pack: unable to create pipe");
-       pid = fork();
-       if (pid < 0)
+       pid_rev_list = fork();
+       if (pid_rev_list < 0)
                die("git-upload-pack: unable to fork git-rev-list");
 
-       if (!pid) {
+       if (!pid_rev_list) {
                int i;
                int args;
                const char **argv;
+               const char **p;
                char *buf;
-               char **p;
 
                if (create_full_pack) {
                        args = 10;
@@ -60,10 +108,10 @@ static void create_pack_file(void)
                argv = (const char **) p;
                buf = xmalloc(args * 45);
 
-               dup2(fd[1], 1);
+               dup2(lp_pipe[1], 1);
                close(0);
-               close(fd[0]);
-               close(fd[1]);
+               close(lp_pipe[0]);
+               close(lp_pipe[1]);
                *p++ = "rev-list";
                *p++ = use_thin_pack ? "--objects-edge" : "--objects";
                if (create_full_pack || MAX_NEEDS <= nr_needs)
@@ -86,11 +134,184 @@ static void create_pack_file(void)
                execv_git_cmd(argv);
                die("git-upload-pack: unable to exec git-rev-list");
        }
-       dup2(fd[0], 0);
-       close(fd[0]);
-       close(fd[1]);
-       execl_git_cmd("pack-objects", "--stdout", NULL);
-       die("git-upload-pack: unable to exec git-pack-objects");
+
+       if (pipe(pu_pipe) < 0)
+               die("git-upload-pack: unable to create pipe");
+       if (pipe(pe_pipe) < 0)
+               die("git-upload-pack: unable to create pipe");
+       pid_pack_objects = fork();
+       if (pid_pack_objects < 0) {
+               /* daemon sets things up to ignore TERM */
+               kill(pid_rev_list, SIGKILL);
+               die("git-upload-pack: unable to fork git-pack-objects");
+       }
+       if (!pid_pack_objects) {
+               dup2(lp_pipe[0], 0);
+               dup2(pu_pipe[1], 1);
+               dup2(pe_pipe[1], 2);
+
+               close(lp_pipe[0]);
+               close(lp_pipe[1]);
+               close(pu_pipe[0]);
+               close(pu_pipe[1]);
+               close(pe_pipe[0]);
+               close(pe_pipe[1]);
+               execl_git_cmd("pack-objects", "--stdout", "--progress", NULL);
+               kill(pid_rev_list, SIGKILL);
+               die("git-upload-pack: unable to exec git-pack-objects");
+       }
+
+       close(lp_pipe[0]);
+       close(lp_pipe[1]);
+
+       /* We read from pe_pipe[0] to capture stderr output for
+        * progress bar, and pu_pipe[0] to capture the pack data.
+        */
+       close(pe_pipe[1]);
+       close(pu_pipe[1]);
+
+       while (1) {
+               const char *who;
+               struct pollfd pfd[2];
+               pid_t pid;
+               int status;
+               ssize_t sz;
+               int pe, pu, pollsize;
+
+               pollsize = 0;
+               pe = pu = -1;
+
+               if (0 <= pu_pipe[0]) {
+                       pfd[pollsize].fd = pu_pipe[0];
+                       pfd[pollsize].events = POLLIN;
+                       pu = pollsize;
+                       pollsize++;
+               }
+               if (0 <= pe_pipe[0]) {
+                       pfd[pollsize].fd = pe_pipe[0];
+                       pfd[pollsize].events = POLLIN;
+                       pe = pollsize;
+                       pollsize++;
+               }
+
+               if (pollsize) {
+                       if (poll(pfd, pollsize, -1) < 0) {
+                               if (errno != EINTR) {
+                                       error("poll failed, resuming: %s",
+                                             strerror(errno));
+                                       sleep(1);
+                               }
+                               continue;
+                       }
+                       if (0 <= pu && (pfd[pu].revents & (POLLIN|POLLHUP))) {
+                               /* Data ready; we keep the last byte
+                                * to ourselves in case we detect
+                                * broken rev-list, so that we can
+                                * leave the stream corrupted.  This
+                                * is unfortunate -- unpack-objects
+                                * would happily accept a valid pack
+                                * data with trailing garbage, so
+                                * appending garbage after we pass all
+                                * the pack data is not good enough to
+                                * signal breakage to downstream.
+                                */
+                               char *cp = data;
+                               ssize_t outsz = 0;
+                               if (0 <= buffered) {
+                                       *cp++ = buffered;
+                                       outsz++;
+                               }
+                               sz = read(pu_pipe[0], cp,
+                                         sizeof(data) - outsz);
+                               if (0 < sz)
+                                               ;
+                               else if (sz == 0) {
+                                       close(pu_pipe[0]);
+                                       pu_pipe[0] = -1;
+                               }
+                               else
+                                       goto fail;
+                               sz += outsz;
+                               if (1 < sz) {
+                                       buffered = data[sz-1] & 0xFF;
+                                       sz--;
+                               }
+                               else
+                                       buffered = -1;
+                               sz = send_client_data(1, data, sz);
+                               if (sz < 0)
+                                       goto fail;
+                       }
+                       if (0 <= pe && (pfd[pe].revents & (POLLIN|POLLHUP))) {
+                               /* Status ready; we ship that in the side-band
+                                * or dump to the standard error.
+                                */
+                               sz = read(pe_pipe[0], progress,
+                                         sizeof(progress));
+                               if (0 < sz)
+                                       send_client_data(2, progress, sz);
+                               else if (sz == 0) {
+                                       close(pe_pipe[0]);
+                                       pe_pipe[0] = -1;
+                               }
+                               else
+                                       goto fail;
+                       }
+               }
+
+               /* See if the children are still there */
+               if (pid_rev_list || pid_pack_objects) {
+                       pid = waitpid(-1, &status, WNOHANG);
+                       if (!pid)
+                               continue;
+                       who = ((pid == pid_rev_list) ? "git-rev-list" :
+                              (pid == pid_pack_objects) ? "git-pack-objects" :
+                              NULL);
+                       if (!who) {
+                               if (pid < 0) {
+                                       error("git-upload-pack: %s",
+                                             strerror(errno));
+                                       goto fail;
+                               }
+                               error("git-upload-pack: we weren't "
+                                     "waiting for %d", pid);
+                               continue;
+                       }
+                       if (!WIFEXITED(status) || WEXITSTATUS(status) > 0) {
+                               error("git-upload-pack: %s died with error.",
+                                     who);
+                               goto fail;
+                       }
+                       if (pid == pid_rev_list)
+                               pid_rev_list = 0;
+                       if (pid == pid_pack_objects)
+                               pid_pack_objects = 0;
+                       if (pid_rev_list || pid_pack_objects)
+                               continue;
+               }
+
+               /* both died happily */
+               if (pollsize)
+                       continue;
+
+               /* flush the data */
+               if (0 <= buffered) {
+                       data[0] = buffered;
+                       sz = send_client_data(1, data, 1);
+                       if (sz < 0)
+                               goto fail;
+                       fprintf(stderr, "flushed.\n");
+               }
+               send_client_data(1, NULL, 0);
+               return;
+       }
+ fail:
+       if (pid_pack_objects)
+               kill(pid_pack_objects, SIGKILL);
+       if (pid_rev_list)
+               kill(pid_rev_list, SIGKILL);
+       send_client_data(3, abort_msg, sizeof(abort_msg));
+       die("git-upload-pack: %s", abort_msg);
 }
 
 static int got_sha1(char *hex, unsigned char *sha1)
@@ -105,7 +326,7 @@ static int got_sha1(char *hex, unsigned char *sha1)
                        o = parse_object(sha1);
                if (!o)
                        die("oops (%s)", sha1_to_hex(sha1));
-               if (o->type == commit_type) {
+               if (o->type == TYPE_COMMIT) {
                        struct commit_list *parents;
                        if (o->flags & THEY_HAVE)
                                return 0;
@@ -197,6 +418,8 @@ static int receive_needs(void)
                        multi_ack = 1;
                if (strstr(line+45, "thin-pack"))
                        use_thin_pack = 1;
+               if (strstr(line+45, "side-band"))
+                       use_sideband = 1;
 
                /* We have sent all our refs already, and the other end
                 * should have chosen out of them; otherwise they are
@@ -218,7 +441,7 @@ static int receive_needs(void)
 
 static int send_ref(const char *refname, const unsigned char *sha1)
 {
-       static char *capabilities = "multi_ack thin-pack";
+       static const char *capabilities = "multi_ack thin-pack side-band";
        struct object *o = parse_object(sha1);
 
        if (!o)
@@ -234,7 +457,7 @@ static int send_ref(const char *refname, const unsigned char *sha1)
                o->flags |= OUR_REF;
                nr_our_refs++;
        }
-       if (o->type == tag_type) {
+       if (o->type == TYPE_TAG) {
                o = deref_tag(o, refname, 0);
                packet_write(1, "%s %s^{}\n", sha1_to_hex(o->sha1), refname);
        }