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