fetch-clone.c

   1 #include "cache.h"
   2 #include "exec_cmd.h"
   3 #include "pkt-line.h"
   4 #include "sideband.h"
   5 #include <sys/wait.h>
   6 #include <sys/time.h>
   7
   8 static int finish_pack(const char *pack_tmp_name, const char *me)
   9 {
  10         int pipe_fd[2];
  11         pid_t pid;
  12         char idx[PATH_MAX];
  13         char final[PATH_MAX];
  14         char hash[41];
  15         unsigned char sha1[20];
  16         char *cp;
  17         int err = 0;
  18
  19         if (pipe(pipe_fd) < 0)
  20                 die("%s: unable to set up pipe", me);
  21
  22         strcpy(idx, pack_tmp_name); /* ".git/objects/pack-XXXXXX" */
  23         cp = strrchr(idx, '/');
  24         memcpy(cp, "/pidx", 5);
  25
  26         pid = fork();
  27         if (pid < 0)
  28                 die("%s: unable to fork off git-index-pack", me);
  29         if (!pid) {
  30                 close(0);
  31                 dup2(pipe_fd[1], 1);
  32                 close(pipe_fd[0]);
  33                 close(pipe_fd[1]);
  34                 execl_git_cmd("index-pack", "-o", idx, pack_tmp_name, NULL);
  35                 error("cannot exec git-index-pack <%s> <%s>",
  36                       idx, pack_tmp_name);
  37                 exit(1);
  38         }
  39         close(pipe_fd[1]);
  40         if (read(pipe_fd[0], hash, 40) != 40) {
  41                 error("%s: unable to read from git-index-pack", me);
  42                 err = 1;
  43         }
  44         close(pipe_fd[0]);
  45
  46         for (;;) {
  47                 int status, code;
  48
  49                 if (waitpid(pid, &status, 0) < 0) {
  50                         if (errno == EINTR)
  51                                 continue;
  52                         error("waitpid failed (%s)", strerror(errno));
  53                         goto error_die;
  54                 }
  55                 if (WIFSIGNALED(status)) {
  56                         int sig = WTERMSIG(status);
  57                         error("git-index-pack died of signal %d", sig);
  58                         goto error_die;
  59                 }
  60                 if (!WIFEXITED(status)) {
  61                         error("git-index-pack died of unnatural causes %d",
  62                               status);
  63                         goto error_die;
  64                 }
  65                 code = WEXITSTATUS(status);
  66                 if (code) {
  67                         error("git-index-pack died with error code %d", code);
  68                         goto error_die;
  69                 }
  70                 if (err)
  71                         goto error_die;
  72                 break;
  73         }
  74         hash[40] = 0;
  75         if (get_sha1_hex(hash, sha1)) {
  76                 error("git-index-pack reported nonsense '%s'", hash);
  77                 goto error_die;
  78         }
  79         /* Now we have pack in pack_tmp_name[], and
  80          * idx in idx[]; rename them to their final names.
  81          */
  82         snprintf(final, sizeof(final),
  83                  "%s/pack/pack-%s.pack", get_object_directory(), hash);
  84         move_temp_to_file(pack_tmp_name, final);
  85         chmod(final, 0444);
  86         snprintf(final, sizeof(final),
  87                  "%s/pack/pack-%s.idx", get_object_directory(), hash);
  88         move_temp_to_file(idx, final);
  89         chmod(final, 0444);
  90         return 0;
  91
  92  error_die:
  93         unlink(idx);
  94         unlink(pack_tmp_name);
  95         exit(1);
  96 }
  97
  98 static pid_t setup_sideband(int sideband, const char *me, int fd[2], int xd[2])
  99 {
 100         pid_t side_pid;
 101
 102         if (!sideband) {
 103                 fd[0] = xd[0];
 104                 fd[1] = xd[1];
 105                 return 0;
 106         }
 107         /* xd[] is talking with upload-pack; subprocess reads from
 108          * xd[0], spits out band#2 to stderr, and feeds us band#1
 109          * through our fd[0].
 110          */
 111         if (pipe(fd) < 0)
 112                 die("%s: unable to set up pipe", me);
 113         side_pid = fork();
 114         if (side_pid < 0)
 115                 die("%s: unable to fork off sideband demultiplexer", me);
 116         if (!side_pid) {
 117                 /* subprocess */
 118                 char buf[LARGE_PACKET_MAX];
 119
 120                 close(fd[0]);
 121                 if (xd[0] != xd[1])
 122                         close(xd[1]);
 123                 if (recv_sideband(me, xd[0], fd[1], 2, buf, sizeof(buf)))
 124                         exit(1);
 125                 exit(0);
 126         }
 127         close(xd[0]);
 128         close(fd[1]);
 129         fd[1] = xd[1];
 130         return side_pid;
 131 }
 132
 133 int receive_unpack_pack(int xd[2], const char *me, int quiet, int sideband)
 134 {
 135         int status;
 136         pid_t pid, side_pid;
 137         int fd[2];
 138
 139         side_pid = setup_sideband(sideband, me, fd, xd);
 140         pid = fork();
 141         if (pid < 0)
 142                 die("%s: unable to fork off git-unpack-objects", me);
 143         if (!pid) {
 144                 dup2(fd[0], 0);
 145                 close(fd[0]);
 146                 close(fd[1]);
 147                 execl_git_cmd("unpack-objects", quiet ? "-q" : NULL, NULL);
 148                 die("git-unpack-objects exec failed");
 149         }
 150         close(fd[0]);
 151         close(fd[1]);
 152         while (waitpid(pid, &status, 0) < 0) {
 153                 if (errno != EINTR)
 154                         die("waiting for git-unpack-objects: %s",
 155                             strerror(errno));
 156         }
 157         if (WIFEXITED(status)) {
 158                 int code = WEXITSTATUS(status);
 159                 if (code)
 160                         die("git-unpack-objects died with error code %d",
 161                             code);
 162                 return 0;
 163         }
 164         if (WIFSIGNALED(status)) {
 165                 int sig = WTERMSIG(status);
 166                 die("git-unpack-objects died of signal %d", sig);
 167         }
 168         die("git-unpack-objects died of unnatural causes %d", status);
 169 }
 170
 171 /*
 172  * We average out the download speed over this many "events", where
 173  * an event is a minimum of about half a second. That way, we get
 174  * a reasonably stable number.
 175  */
 176 #define NR_AVERAGE (4)
 177
 178 /*
 179  * A "binary msec" is a power-of-two-msec, aka 1/1024th of a second.
 180  * Keeping the time in that format means that "bytes / msecs" means
 181  * the same as kB/s (modulo rounding).
 182  *
 183  * 1000512 is a magic number (usecs in a second, rounded up by half
 184  * of 1024, to make "rounding" come out right ;)
 185  */
 186 #define usec_to_binarymsec(x) ((int)(x) / (1000512 >> 10))
 187
 188 int receive_keep_pack(int xd[2], const char *me, int quiet, int sideband)
 189 {
 190         char tmpfile[PATH_MAX];
 191         int ofd, ifd, fd[2];
 192         unsigned long total;
 193         static struct timeval prev_tv;
 194         struct average {
 195                 unsigned long bytes;
 196                 unsigned long time;
 197         } download[NR_AVERAGE] = { {0, 0}, };
 198         unsigned long avg_bytes, avg_time;
 199         int idx = 0;
 200
 201         setup_sideband(sideband, me, fd, xd);
 202
 203         ifd = fd[0];
 204         snprintf(tmpfile, sizeof(tmpfile),
 205                  "%s/pack/tmp-XXXXXX", get_object_directory());
 206         ofd = mkstemp(tmpfile);
 207         if (ofd < 0)
 208                 return error("unable to create temporary file %s", tmpfile);
 209
 210         gettimeofday(&prev_tv, NULL);
 211         total = 0;
 212         avg_bytes = 0;
 213         avg_time = 0;
 214         while (1) {
 215                 char buf[8192];
 216                 ssize_t sz, wsz, pos;
 217                 sz = read(ifd, buf, sizeof(buf));
 218                 if (sz == 0)
 219                         break;
 220                 if (sz < 0) {
 221                         if (errno != EINTR && errno != EAGAIN) {
 222                                 error("error reading pack (%s)", strerror(errno));
 223                                 close(ofd);
 224                                 unlink(tmpfile);
 225                                 return -1;
 226                         }
 227                         sz = 0;
 228                 }
 229                 pos = 0;
 230                 while (pos < sz) {
 231                         wsz = write(ofd, buf + pos, sz - pos);
 232                         if (wsz < 0) {
 233                                 error("error writing pack (%s)",
 234                                       strerror(errno));
 235                                 close(ofd);
 236                                 unlink(tmpfile);
 237                                 return -1;
 238                         }
 239                         pos += wsz;
 240                 }
 241                 total += sz;
 242                 if (!quiet) {
 243                         static unsigned long last;
 244                         struct timeval tv;
 245                         unsigned long diff = total - last;
 246                         /* not really "msecs", but a power-of-two millisec (1/1024th of a sec) */
 247                         unsigned long msecs;
 248
 249                         gettimeofday(&tv, NULL);
 250                         msecs = tv.tv_sec - prev_tv.tv_sec;
 251                         msecs <<= 10;
 252                         msecs += usec_to_binarymsec(tv.tv_usec - prev_tv.tv_usec);
 253
 254                         if (msecs > 500) {
 255                                 prev_tv = tv;
 256                                 last = total;
 257
 258                                 /* Update averages ..*/
 259                                 avg_bytes += diff;
 260                                 avg_time += msecs;
 261                                 avg_bytes -= download[idx].bytes;
 262                                 avg_time -= download[idx].time;
 263                                 download[idx].bytes = diff;
 264                                 download[idx].time = msecs;
 265                                 idx++;
 266                                 if (idx >= NR_AVERAGE)
 267                                         idx = 0;
 268
 269                                 fprintf(stderr, "%4lu.%03luMB  (%lu kB/s)      \r",
 270                                         total >> 20,
 271                                         1000*((total >> 10) & 1023)>>10,
 272                                         avg_bytes / avg_time );
 273                         }
 274                 }
 275         }
 276         close(ofd);
 277         return finish_pack(tmpfile, me);
 278 }