pull.c

   1 #include "pull.h"
   2
   3 #include "cache.h"
   4 #include "commit.h"
   5 #include "tree.h"
   6 #include "tag.h"
   7 #include "blob.h"
   8 #include "refs.h"
   9
  10 const char *write_ref = NULL;
  11
  12 const unsigned char *current_ref = NULL;
  13
  14 int get_tree = 0;
  15 int get_history = 0;
  16 int get_all = 0;
  17 int get_verbosely = 0;
  18 static unsigned char current_commit_sha1[20];
  19
  20 void pull_say(const char *fmt, const char *hex)
  21 {
  22         if (get_verbosely)
  23                 fprintf(stderr, fmt, hex);
  24 }
  25
  26 static void report_missing(const char *what, const unsigned char *missing)
  27 {
  28         char missing_hex[41];
  29
  30         strcpy(missing_hex, sha1_to_hex(missing));;
  31         fprintf(stderr,
  32                 "Cannot obtain needed %s %s\nwhile processing commit %s.\n",
  33                 what, missing_hex, sha1_to_hex(current_commit_sha1));
  34 }
  35
  36 static int make_sure_we_have_it(const char *what, unsigned char *sha1)
  37 {
  38         int status = 0;
  39
  40         if (!has_sha1_file(sha1)) {
  41                 status = fetch(sha1);
  42                 if (status && what)
  43                         report_missing(what, sha1);
  44         }
  45         return status;
  46 }
  47
  48 static int process(unsigned char *sha1, const char *type);
  49
  50 static int process_tree(struct tree *tree)
  51 {
  52         struct tree_entry_list *entries;
  53
  54         if (parse_tree(tree))
  55                 return -1;
  56
  57         for (entries = tree->entries; entries; entries = entries->next) {
  58                 if (process(entries->item.any->sha1,
  59                             entries->directory ? tree_type : blob_type))
  60                         return -1;
  61         }
  62         return 0;
  63 }
  64
  65 static int process_commit(struct commit *commit)
  66 {
  67         if (parse_commit(commit))
  68                 return -1;
  69
  70         memcpy(current_commit_sha1, commit->object.sha1, 20);
  71
  72         if (get_tree) {
  73                 if (process(commit->tree->object.sha1, tree_type))
  74                         return -1;
  75                 if (!get_all)
  76                         get_tree = 0;
  77         }
  78         if (get_history) {
  79                 struct commit_list *parents = commit->parents;
  80                 for (; parents; parents = parents->next) {
  81                         if (has_sha1_file(parents->item->object.sha1))
  82                                 continue;
  83                         if (process(parents->item->object.sha1,
  84                                     commit_type))
  85                                 return -1;
  86                 }
  87         }
  88         return 0;
  89 }
  90
  91 static int process_tag(struct tag *tag)
  92 {
  93         if (parse_tag(tag))
  94                 return -1;
  95         return process(tag->tagged->sha1, NULL);
  96 }
  97
  98 static struct object_list *process_queue = NULL;
  99 static struct object_list **process_queue_end = &process_queue;
 100
 101 static int process_object(struct object *obj)
 102 {
 103         if (obj->type == commit_type) {
 104                 if (process_commit((struct commit *)obj))
 105                         return -1;
 106                 return 0;
 107         }
 108         if (obj->type == tree_type) {
 109                 if (process_tree((struct tree *)obj))
 110                         return -1;
 111                 return 0;
 112         }
 113         if (obj->type == blob_type) {
 114                 return 0;
 115         }
 116         if (obj->type == tag_type) {
 117                 if (process_tag((struct tag *)obj))
 118                         return -1;
 119                 return 0;
 120         }
 121         return error("Unable to determine requirements "
 122                      "of type %s for %s",
 123                      obj->type, sha1_to_hex(obj->sha1));
 124 }
 125
 126 static int process(unsigned char *sha1, const char *type)
 127 {
 128         struct object *obj = lookup_object_type(sha1, type);
 129         if (has_sha1_file(sha1)) {
 130                 parse_object(sha1);
 131                 /* We already have it, so we should scan it now. */
 132                 return process_object(obj);
 133         }
 134         if (object_list_contains(process_queue, obj))
 135                 return 0;
 136         object_list_insert(obj, process_queue_end);
 137         process_queue_end = &(*process_queue_end)->next;
 138
 139         //fprintf(stderr, "prefetch %s\n", sha1_to_hex(sha1));
 140         prefetch(sha1);
 141
 142         return 0;
 143 }
 144
 145 static int loop(void)
 146 {
 147         while (process_queue) {
 148                 struct object *obj = process_queue->item;
 149                 /*
 150                 fprintf(stderr, "%d objects to pull\n",
 151                         object_list_length(process_queue));
 152                 */
 153                 process_queue = process_queue->next;
 154                 if (!process_queue)
 155                         process_queue_end = &process_queue;
 156
 157                 //fprintf(stderr, "fetch %s\n", sha1_to_hex(obj->sha1));
 158
 159                 if (make_sure_we_have_it(obj->type ? obj->type : "object",
 160                                          obj->sha1))
 161                         return -1;
 162                 if (!obj->type)
 163                         parse_object(obj->sha1);
 164                 if (process_object(obj))
 165                         return -1;
 166         }
 167         return 0;
 168 }
 169
 170 static int interpret_target(char *target, unsigned char *sha1)
 171 {
 172         if (!get_sha1_hex(target, sha1))
 173                 return 0;
 174         if (!check_ref_format(target)) {
 175                 if (!fetch_ref(target, sha1)) {
 176                         return 0;
 177                 }
 178         }
 179         return -1;
 180 }
 181
 182
 183 int pull(char *target)
 184 {
 185         unsigned char sha1[20];
 186         int fd = -1;
 187
 188         if (write_ref && current_ref) {
 189                 fd = lock_ref_sha1(write_ref, current_ref);
 190                 if (fd < 0)
 191                         return -1;
 192         }
 193
 194         if (interpret_target(target, sha1))
 195                 return error("Could not interpret %s as something to pull",
 196                              target);
 197         if (process(sha1, NULL))
 198                 return -1;
 199         if (loop())
 200                 return -1;
 201
 202         if (write_ref) {
 203                 if (current_ref) {
 204                         write_ref_sha1(write_ref, fd, sha1);
 205                 } else {
 206                         write_ref_sha1_unlocked(write_ref, sha1);
 207                 }
 208         }
 209         return 0;
 210 }