fetch-clone.c

   1 #include "cache.h"
   2 #include "exec_cmd.h"
   3 #include "pkt-line.h"
   4 #include <sys/wait.h>
   5 #include <sys/time.h>
   6
   7 static int finish_pack(const char *pack_tmp_name, const char *me)
   8 {
   9         int pipe_fd[2];
  10         pid_t pid;
  11         char idx[PATH_MAX];
  12         char final[PATH_MAX];
  13         char hash[41];
  14         unsigned char sha1[20];
  15         char *cp;
  16         int err = 0;
  17
  18         if (pipe(pipe_fd) < 0)
  19                 die("%s: unable to set up pipe", me);
  20
  21         strcpy(idx, pack_tmp_name); /* ".git/objects/pack-XXXXXX" */
  22         cp = strrchr(idx, '/');
  23         memcpy(cp, "/pidx", 5);
  24
  25         pid = fork();
  26         if (pid < 0)
  27                 die("%s: unable to fork off git-index-pack", me);
  28         if (!pid) {
  29                 close(0);
  30                 dup2(pipe_fd[1], 1);
  31                 close(pipe_fd[0]);
  32                 close(pipe_fd[1]);
  33                 execl_git_cmd("index-pack", "-o", idx, pack_tmp_name, NULL);
  34                 error("cannot exec git-index-pack <%s> <%s>",
  35                       idx, pack_tmp_name);
  36                 exit(1);
  37         }
  38         close(pipe_fd[1]);
  39         if (read(pipe_fd[0], hash, 40) != 40) {
  40                 error("%s: unable to read from git-index-pack", me);
  41                 err = 1;
  42         }
  43         close(pipe_fd[0]);
  44
  45         for (;;) {
  46                 int status, code;
  47                 int retval = waitpid(pid, &status, 0);
  48
  49                 if (retval < 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                 close(fd[0]);
 119                 if (xd[0] != xd[1])
 120                         close(xd[1]);
 121                 while (1) {
 122                         char buf[1024];
 123                         int len = packet_read_line(xd[0], buf, sizeof(buf));
 124                         if (len == 0)
 125                                 break;
 126                         if (len < 1)
 127                                 die("%s: protocol error: no band designator",
 128                                     me);
 129                         len--;
 130                         switch (buf[0] & 0xFF) {
 131                         case 3:
 132                                 safe_write(2, buf+1, len);
 133                                 fprintf(stderr, "\n");
 134                                 exit(1);
 135                         case 2:
 136                                 safe_write(2, buf+1, len);
 137                                 continue;
 138                         case 1:
 139                                 safe_write(fd[1], buf+1, len);
 140                                 continue;
 141                         default:
 142                                 die("%s: protocol error: bad band #%d",
 143                                     me, (buf[0] & 0xFF));
 144                         }
 145                 }
 146                 exit(0);
 147         }
 148         close(xd[0]);
 149         close(fd[1]);
 150         fd[1] = xd[1];
 151         return side_pid;
 152 }
 153
 154 int receive_unpack_pack(int xd[2], const char *me, int quiet, int sideband)
 155 {
 156         int status;
 157         pid_t pid, side_pid;
 158         int fd[2];
 159
 160         side_pid = setup_sideband(sideband, me, fd, xd);
 161         pid = fork();
 162         if (pid < 0)
 163                 die("%s: unable to fork off git-unpack-objects", me);
 164         if (!pid) {
 165                 dup2(fd[0], 0);
 166                 close(fd[0]);
 167                 close(fd[1]);
 168                 execl_git_cmd("unpack-objects", quiet ? "-q" : NULL, NULL);
 169                 die("git-unpack-objects exec failed");
 170         }
 171         close(fd[0]);
 172         close(fd[1]);
 173         while (waitpid(pid, &status, 0) < 0) {
 174                 if (errno != EINTR)
 175                         die("waiting for git-unpack-objects: %s",
 176                             strerror(errno));
 177         }
 178         if (WIFEXITED(status)) {
 179                 int code = WEXITSTATUS(status);
 180                 if (code)
 181                         die("git-unpack-objects died with error code %d",
 182                             code);
 183                 return 0;
 184         }
 185         if (WIFSIGNALED(status)) {
 186                 int sig = WTERMSIG(status);
 187                 die("git-unpack-objects died of signal %d", sig);
 188         }
 189         die("git-unpack-objects died of unnatural causes %d", status);
 190 }
 191
 192 /*
 193  * We average out the download speed over this many "events", where
 194  * an event is a minimum of about half a second. That way, we get
 195  * a reasonably stable number.
 196  */
 197 #define NR_AVERAGE (4)
 198
 199 /*
 200  * A "binary msec" is a power-of-two-msec, aka 1/1024th of a second.
 201  * Keeing the time in that format means that "bytes / msecs" means
 202  * is the same as kB/s (modulo rounding).
 203  *
 204  * 1000512 is a magic number (usecs in a second, rounded up by half
 205  * of 1024, to make "rounding" come out right ;)
 206  */
 207 #define usec_to_binarymsec(x) ((int)(x) / (1000512 >> 10))
 208
 209 int receive_keep_pack(int xd[2], const char *me, int quiet, int sideband)
 210 {
 211         char tmpfile[PATH_MAX];
 212         int ofd, ifd, fd[2];
 213         unsigned long total;
 214         static struct timeval prev_tv;
 215         struct average {
 216                 unsigned long bytes;
 217                 unsigned long time;
 218         } download[NR_AVERAGE] = { {0, 0}, };
 219         unsigned long avg_bytes, avg_time;
 220         int idx = 0;
 221
 222         setup_sideband(sideband, me, fd, xd);
 223
 224         ifd = fd[0];
 225         snprintf(tmpfile, sizeof(tmpfile),
 226                  "%s/pack/tmp-XXXXXX", get_object_directory());
 227         ofd = mkstemp(tmpfile);
 228         if (ofd < 0)
 229                 return error("unable to create temporary file %s", tmpfile);
 230
 231         gettimeofday(&prev_tv, NULL);
 232         total = 0;
 233         avg_bytes = 0;
 234         avg_time = 0;
 235         while (1) {
 236                 char buf[8192];
 237                 ssize_t sz, wsz, pos;
 238                 sz = read(ifd, buf, sizeof(buf));
 239                 if (sz == 0)
 240                         break;
 241                 if (sz < 0) {
 242                         if (errno != EINTR && errno != EAGAIN) {
 243                                 error("error reading pack (%s)", strerror(errno));
 244                                 close(ofd);
 245                                 unlink(tmpfile);
 246                                 return -1;
 247                         }
 248                         sz = 0;
 249                 }
 250                 pos = 0;
 251                 while (pos < sz) {
 252                         wsz = write(ofd, buf + pos, sz - pos);
 253                         if (wsz < 0) {
 254                                 error("error writing pack (%s)",
 255                                       strerror(errno));
 256                                 close(ofd);
 257                                 unlink(tmpfile);
 258                                 return -1;
 259                         }
 260                         pos += wsz;
 261                 }
 262                 total += sz;
 263                 if (!quiet) {
 264                         static unsigned long last;
 265                         struct timeval tv;
 266                         unsigned long diff = total - last;
 267                         /* not really "msecs", but a power-of-two millisec (1/1024th of a sec) */
 268                         unsigned long msecs;
 269
 270                         gettimeofday(&tv, NULL);
 271                         msecs = tv.tv_sec - prev_tv.tv_sec;
 272                         msecs <<= 10;
 273                         msecs += usec_to_binarymsec(tv.tv_usec - prev_tv.tv_usec);
 274
 275                         if (msecs > 500) {
 276                                 prev_tv = tv;
 277                                 last = total;
 278
 279                                 /* Update averages ..*/
 280                                 avg_bytes += diff;
 281                                 avg_time += msecs;
 282                                 avg_bytes -= download[idx].bytes;
 283                                 avg_time -= download[idx].time;
 284                                 download[idx].bytes = diff;
 285                                 download[idx].time = msecs;
 286                                 idx++;
 287                                 if (idx >= NR_AVERAGE)
 288                                         idx = 0;
 289
 290                                 fprintf(stderr, "%4lu.%03luMB  (%lu kB/s)      \r",
 291                                         total >> 20,
 292                                         1000*((total >> 10) & 1023)>>10,
 293                                         avg_bytes / avg_time );
 294                         }
 295                 }
 296         }
 297         close(ofd);
 298         return finish_pack(tmpfile, me);
 299 }