transport-helper.c

   1 #include "cache.h"
   2 #include "transport.h"
   3
   4 #include "run-command.h"
   5 #include "commit.h"
   6 #include "diff.h"
   7 #include "revision.h"
   8 #include "remote.h"
   9
  10 struct helper_data
  11 {
  12         const char *name;
  13         struct child_process *helper;
  14         unsigned fetch : 1;
  15         unsigned import : 1;
  16         /* These go from remote name (as in "list") to private name */
  17         struct refspec *refspecs;
  18         int refspec_nr;
  19 };
  20
  21 static struct child_process *get_helper(struct transport *transport)
  22 {
  23         struct helper_data *data = transport->data;
  24         struct strbuf buf = STRBUF_INIT;
  25         struct child_process *helper;
  26         FILE *file;
  27         const char **refspecs = NULL;
  28         int refspec_nr = 0;
  29         int refspec_alloc = 0;
  30
  31         if (data->helper)
  32                 return data->helper;
  33
  34         helper = xcalloc(1, sizeof(*helper));
  35         helper->in = -1;
  36         helper->out = -1;
  37         helper->err = 0;
  38         helper->argv = xcalloc(4, sizeof(*helper->argv));
  39         strbuf_addf(&buf, "remote-%s", data->name);
  40         helper->argv[0] = strbuf_detach(&buf, NULL);
  41         helper->argv[1] = transport->remote->name;
  42         helper->argv[2] = transport->url;
  43         helper->git_cmd = 1;
  44         if (start_command(helper))
  45                 die("Unable to run helper: git %s", helper->argv[0]);
  46         data->helper = helper;
  47
  48         write_str_in_full(helper->in, "capabilities\n");
  49
  50         file = xfdopen(helper->out, "r");
  51         while (1) {
  52                 if (strbuf_getline(&buf, file, '\n') == EOF)
  53                         exit(128); /* child died, message supplied already */
  54
  55                 if (!*buf.buf)
  56                         break;
  57                 if (!strcmp(buf.buf, "fetch"))
  58                         data->fetch = 1;
  59                 if (!strcmp(buf.buf, "import"))
  60                         data->import = 1;
  61                 if (!data->refspecs && !prefixcmp(buf.buf, "refspec ")) {
  62                         ALLOC_GROW(refspecs,
  63                                    refspec_nr + 1,
  64                                    refspec_alloc);
  65                         refspecs[refspec_nr++] = strdup(buf.buf + strlen("refspec "));
  66                 }
  67         }
  68         if (refspecs) {
  69                 int i;
  70                 data->refspec_nr = refspec_nr;
  71                 data->refspecs = parse_fetch_refspec(refspec_nr, refspecs);
  72                 for (i = 0; i < refspec_nr; i++) {
  73                         free((char *)refspecs[i]);
  74                 }
  75                 free(refspecs);
  76         }
  77         return data->helper;
  78 }
  79
  80 static int disconnect_helper(struct transport *transport)
  81 {
  82         struct helper_data *data = transport->data;
  83         if (data->helper) {
  84                 write_str_in_full(data->helper->in, "\n");
  85                 close(data->helper->in);
  86                 finish_command(data->helper);
  87                 free((char *)data->helper->argv[0]);
  88                 free(data->helper->argv);
  89                 free(data->helper);
  90                 data->helper = NULL;
  91         }
  92         return 0;
  93 }
  94
  95 static int release_helper(struct transport *transport)
  96 {
  97         struct helper_data *data = transport->data;
  98         free_refspec(data->refspec_nr, data->refspecs);
  99         data->refspecs = NULL;
 100         disconnect_helper(transport);
 101         free(transport->data);
 102         return 0;
 103 }
 104
 105 static int fetch_with_fetch(struct transport *transport,
 106                             int nr_heads, struct ref **to_fetch)
 107 {
 108         struct child_process *helper = get_helper(transport);
 109         FILE *file = xfdopen(helper->out, "r");
 110         int i;
 111         struct strbuf buf = STRBUF_INIT;
 112
 113         for (i = 0; i < nr_heads; i++) {
 114                 const struct ref *posn = to_fetch[i];
 115                 if (posn->status & REF_STATUS_UPTODATE)
 116                         continue;
 117
 118                 strbuf_addf(&buf, "fetch %s %s\n",
 119                             sha1_to_hex(posn->old_sha1), posn->name);
 120                 write_in_full(helper->in, buf.buf, buf.len);
 121                 strbuf_reset(&buf);
 122
 123                 if (strbuf_getline(&buf, file, '\n') == EOF)
 124                         exit(128); /* child died, message supplied already */
 125         }
 126         return 0;
 127 }
 128
 129 static int get_importer(struct transport *transport, struct child_process *fastimport)
 130 {
 131         struct child_process *helper = get_helper(transport);
 132         memset(fastimport, 0, sizeof(*fastimport));
 133         fastimport->in = helper->out;
 134         fastimport->argv = xcalloc(5, sizeof(*fastimport->argv));
 135         fastimport->argv[0] = "fast-import";
 136         fastimport->argv[1] = "--quiet";
 137
 138         fastimport->git_cmd = 1;
 139         return start_command(fastimport);
 140 }
 141
 142 static int fetch_with_import(struct transport *transport,
 143                              int nr_heads, struct ref **to_fetch)
 144 {
 145         struct child_process fastimport;
 146         struct child_process *helper = get_helper(transport);
 147         struct helper_data *data = transport->data;
 148         int i;
 149         struct ref *posn;
 150         struct strbuf buf = STRBUF_INIT;
 151
 152         if (get_importer(transport, &fastimport))
 153                 die("Couldn't run fast-import");
 154
 155         for (i = 0; i < nr_heads; i++) {
 156                 posn = to_fetch[i];
 157                 if (posn->status & REF_STATUS_UPTODATE)
 158                         continue;
 159
 160                 strbuf_addf(&buf, "import %s\n", posn->name);
 161                 write_in_full(helper->in, buf.buf, buf.len);
 162                 strbuf_reset(&buf);
 163         }
 164         disconnect_helper(transport);
 165         finish_command(&fastimport);
 166
 167         for (i = 0; i < nr_heads; i++) {
 168                 char *private;
 169                 posn = to_fetch[i];
 170                 if (posn->status & REF_STATUS_UPTODATE)
 171                         continue;
 172                 if (data->refspecs)
 173                         private = apply_refspecs(data->refspecs, data->refspec_nr, posn->name);
 174                 else
 175                         private = strdup(posn->name);
 176                 read_ref(private, posn->old_sha1);
 177                 free(private);
 178         }
 179         return 0;
 180 }
 181
 182 static int fetch(struct transport *transport,
 183                  int nr_heads, struct ref **to_fetch)
 184 {
 185         struct helper_data *data = transport->data;
 186         int i, count;
 187
 188         count = 0;
 189         for (i = 0; i < nr_heads; i++)
 190                 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
 191                         count++;
 192
 193         if (!count)
 194                 return 0;
 195
 196         if (data->fetch)
 197                 return fetch_with_fetch(transport, nr_heads, to_fetch);
 198
 199         if (data->import)
 200                 return fetch_with_import(transport, nr_heads, to_fetch);
 201
 202         return -1;
 203 }
 204
 205 static struct ref *get_refs_list(struct transport *transport, int for_push)
 206 {
 207         struct child_process *helper;
 208         struct ref *ret = NULL;
 209         struct ref **tail = &ret;
 210         struct ref *posn;
 211         struct strbuf buf = STRBUF_INIT;
 212         FILE *file;
 213
 214         helper = get_helper(transport);
 215
 216         write_str_in_full(helper->in, "list\n");
 217
 218         file = xfdopen(helper->out, "r");
 219         while (1) {
 220                 char *eov, *eon;
 221                 if (strbuf_getline(&buf, file, '\n') == EOF)
 222                         exit(128); /* child died, message supplied already */
 223
 224                 if (!*buf.buf)
 225                         break;
 226
 227                 eov = strchr(buf.buf, ' ');
 228                 if (!eov)
 229                         die("Malformed response in ref list: %s", buf.buf);
 230                 eon = strchr(eov + 1, ' ');
 231                 *eov = '\0';
 232                 if (eon)
 233                         *eon = '\0';
 234                 *tail = alloc_ref(eov + 1);
 235                 if (buf.buf[0] == '@')
 236                         (*tail)->symref = xstrdup(buf.buf + 1);
 237                 else if (buf.buf[0] != '?')
 238                         get_sha1_hex(buf.buf, (*tail)->old_sha1);
 239                 tail = &((*tail)->next);
 240         }
 241         strbuf_release(&buf);
 242
 243         for (posn = ret; posn; posn = posn->next)
 244                 resolve_remote_symref(posn, ret);
 245
 246         return ret;
 247 }
 248
 249 int transport_helper_init(struct transport *transport, const char *name)
 250 {
 251         struct helper_data *data = xcalloc(sizeof(*data), 1);
 252         data->name = name;
 253
 254         transport->data = data;
 255         transport->get_refs_list = get_refs_list;
 256         transport->fetch = fetch;
 257         transport->disconnect = release_helper;
 258         return 0;
 259 }