protocol.c

   1 #include "cache.h"
   2 #include "config.h"
   3 #include "protocol.h"
   4
   5 static enum protocol_version parse_protocol_version(const char *value)
   6 {
   7         if (!strcmp(value, "0"))
   8                 return protocol_v0;
   9         else if (!strcmp(value, "1"))
  10                 return protocol_v1;
  11         else if (!strcmp(value, "2"))
  12                 return protocol_v2;
  13         else
  14                 return protocol_unknown_version;
  15 }
  16
  17 enum protocol_version get_protocol_version_config(void)
  18 {
  19         const char *value;
  20         if (!git_config_get_string_const("protocol.version", &value)) {
  21                 enum protocol_version version = parse_protocol_version(value);
  22
  23                 if (version == protocol_unknown_version)
  24                         die("unknown value for config 'protocol.version': %s",
  25                             value);
  26
  27                 return version;
  28         }
  29
  30         return protocol_v0;
  31 }
  32
  33 enum protocol_version determine_protocol_version_server(void)
  34 {
  35         const char *git_protocol = getenv(GIT_PROTOCOL_ENVIRONMENT);
  36         enum protocol_version version = protocol_v0;
  37
  38         /*
  39          * Determine which protocol version the client has requested.  Since
  40          * multiple 'version' keys can be sent by the client, indicating that
  41          * the client is okay to speak any of them, select the greatest version
  42          * that the client has requested.  This is due to the assumption that
  43          * the most recent protocol version will be the most state-of-the-art.
  44          */
  45         if (git_protocol) {
  46                 struct string_list list = STRING_LIST_INIT_DUP;
  47                 const struct string_list_item *item;
  48                 string_list_split(&list, git_protocol, ':', -1);
  49
  50                 for_each_string_list_item(item, &list) {
  51                         const char *value;
  52                         enum protocol_version v;
  53
  54                         if (skip_prefix(item->string, "version=", &value)) {
  55                                 v = parse_protocol_version(value);
  56                                 if (v > version)
  57                                         version = v;
  58                         }
  59                 }
  60
  61                 string_list_clear(&list, 0);
  62         }
  63
  64         return version;
  65 }
  66
  67 enum protocol_version determine_protocol_version_client(const char *server_response)
  68 {
  69         enum protocol_version version = protocol_v0;
  70
  71         if (skip_prefix(server_response, "version ", &server_response)) {
  72                 version = parse_protocol_version(server_response);
  73
  74                 if (version == protocol_unknown_version)
  75                         die("server is speaking an unknown protocol");
  76                 if (version == protocol_v0)
  77                         die("protocol error: server explicitly said version 0");
  78         }
  79
  80         return version;
  81 }