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
   9 struct helper_data
  10 {
  11         const char *name;
  12         struct child_process *helper;
  13         unsigned fetch : 1;
  14 };
  15
  16 static struct child_process *get_helper(struct transport *transport)
  17 {
  18         struct helper_data *data = transport->data;
  19         struct strbuf buf = STRBUF_INIT;
  20         struct child_process *helper;
  21         FILE *file;
  22
  23         if (data->helper)
  24                 return data->helper;
  25
  26         helper = xcalloc(1, sizeof(*helper));
  27         helper->in = -1;
  28         helper->out = -1;
  29         helper->err = 0;
  30         helper->argv = xcalloc(4, sizeof(*helper->argv));
  31         strbuf_addf(&buf, "remote-%s", data->name);
  32         helper->argv[0] = strbuf_detach(&buf, NULL);
  33         helper->argv[1] = transport->remote->name;
  34         helper->argv[2] = transport->url;
  35         helper->git_cmd = 1;
  36         if (start_command(helper))
  37                 die("Unable to run helper: git %s", helper->argv[0]);
  38         data->helper = helper;
  39
  40         write_str_in_full(helper->in, "capabilities\n");
  41
  42         file = xfdopen(helper->out, "r");
  43         while (1) {
  44                 if (strbuf_getline(&buf, file, '\n') == EOF)
  45                         exit(128); /* child died, message supplied already */
  46
  47                 if (!*buf.buf)
  48                         break;
  49                 if (!strcmp(buf.buf, "fetch"))
  50                         data->fetch = 1;
  51         }
  52         return data->helper;
  53 }
  54
  55 static int disconnect_helper(struct transport *transport)
  56 {
  57         struct helper_data *data = transport->data;
  58         if (data->helper) {
  59                 write_str_in_full(data->helper->in, "\n");
  60                 close(data->helper->in);
  61                 finish_command(data->helper);
  62                 free((char *)data->helper->argv[0]);
  63                 free(data->helper->argv);
  64                 free(data->helper);
  65                 data->helper = NULL;
  66         }
  67         return 0;
  68 }
  69
  70 static int release_helper(struct transport *transport)
  71 {
  72         disconnect_helper(transport);
  73         free(transport->data);
  74         return 0;
  75 }
  76
  77 static int fetch_with_fetch(struct transport *transport,
  78                             int nr_heads, struct ref **to_fetch)
  79 {
  80         struct child_process *helper = get_helper(transport);
  81         FILE *file = xfdopen(helper->out, "r");
  82         int i;
  83         struct strbuf buf = STRBUF_INIT;
  84
  85         for (i = 0; i < nr_heads; i++) {
  86                 const struct ref *posn = to_fetch[i];
  87                 if (posn->status & REF_STATUS_UPTODATE)
  88                         continue;
  89
  90                 strbuf_addf(&buf, "fetch %s %s\n",
  91                             sha1_to_hex(posn->old_sha1), posn->name);
  92                 write_in_full(helper->in, buf.buf, buf.len);
  93                 strbuf_reset(&buf);
  94
  95                 if (strbuf_getline(&buf, file, '\n') == EOF)
  96                         exit(128); /* child died, message supplied already */
  97         }
  98         return 0;
  99 }
 100
 101 static int fetch(struct transport *transport,
 102                  int nr_heads, struct ref **to_fetch)
 103 {
 104         struct helper_data *data = transport->data;
 105         int i, count;
 106
 107         count = 0;
 108         for (i = 0; i < nr_heads; i++)
 109                 if (!(to_fetch[i]->status & REF_STATUS_UPTODATE))
 110                         count++;
 111
 112         if (!count)
 113                 return 0;
 114
 115         if (data->fetch)
 116                 return fetch_with_fetch(transport, nr_heads, to_fetch);
 117
 118         return -1;
 119 }
 120
 121 static struct ref *get_refs_list(struct transport *transport, int for_push)
 122 {
 123         struct child_process *helper;
 124         struct ref *ret = NULL;
 125         struct ref **tail = &ret;
 126         struct ref *posn;
 127         struct strbuf buf = STRBUF_INIT;
 128         FILE *file;
 129
 130         helper = get_helper(transport);
 131
 132         write_str_in_full(helper->in, "list\n");
 133
 134         file = xfdopen(helper->out, "r");
 135         while (1) {
 136                 char *eov, *eon;
 137                 if (strbuf_getline(&buf, file, '\n') == EOF)
 138                         exit(128); /* child died, message supplied already */
 139
 140                 if (!*buf.buf)
 141                         break;
 142
 143                 eov = strchr(buf.buf, ' ');
 144                 if (!eov)
 145                         die("Malformed response in ref list: %s", buf.buf);
 146                 eon = strchr(eov + 1, ' ');
 147                 *eov = '\0';
 148                 if (eon)
 149                         *eon = '\0';
 150                 *tail = alloc_ref(eov + 1);
 151                 if (buf.buf[0] == '@')
 152                         (*tail)->symref = xstrdup(buf.buf + 1);
 153                 else if (buf.buf[0] != '?')
 154                         get_sha1_hex(buf.buf, (*tail)->old_sha1);
 155                 tail = &((*tail)->next);
 156         }
 157         strbuf_release(&buf);
 158
 159         for (posn = ret; posn; posn = posn->next)
 160                 resolve_remote_symref(posn, ret);
 161
 162         return ret;
 163 }
 164
 165 int transport_helper_init(struct transport *transport, const char *name)
 166 {
 167         struct helper_data *data = xcalloc(sizeof(*data), 1);
 168         data->name = name;
 169
 170         transport->data = data;
 171         transport->get_refs_list = get_refs_list;
 172         transport->fetch = fetch;
 173         transport->disconnect = release_helper;
 174         return 0;
 175 }