protocol.c

   1 #include "git-compat-util.h"
   2 #include "config.h"
   3 #include "environment.h"
   4 #include "protocol.h"
   5 #include "trace2.h"
   6
   7 static enum protocol_version parse_protocol_version(const char *value)
   8 {
   9         if (!strcmp(value, "0"))
  10                 return protocol_v0;
  11         else if (!strcmp(value, "1"))
  12                 return protocol_v1;
  13         else if (!strcmp(value, "2"))
  14                 return protocol_v2;
  15         else
  16                 return protocol_unknown_version;
  17 }
  18
  19 enum protocol_version get_protocol_version_config(void)
  20 {
  21         const char *value;
  22         const char *git_test_k = "GIT_TEST_PROTOCOL_VERSION";
  23         const char *git_test_v;
  24
  25         if (!git_config_get_string_tmp("protocol.version", &value)) {
  26                 enum protocol_version version = parse_protocol_version(value);
  27
  28                 if (version == protocol_unknown_version)
  29                         die("unknown value for config 'protocol.version': %s",
  30                             value);
  31
  32                 return version;
  33         }
  34
  35         git_test_v = getenv(git_test_k);
  36         if (git_test_v && *git_test_v) {
  37                 enum protocol_version env = parse_protocol_version(git_test_v);
  38
  39                 if (env == protocol_unknown_version)
  40                         die("unknown value for %s: %s", git_test_k, git_test_v);
  41                 return env;
  42         }
  43
  44         return protocol_v2;
  45 }
  46
  47 enum protocol_version determine_protocol_version_server(void)
  48 {
  49         const char *git_protocol = getenv(GIT_PROTOCOL_ENVIRONMENT);
  50         enum protocol_version version = protocol_v0;
  51
  52         /*
  53          * Determine which protocol version the client has requested.  Since
  54          * multiple 'version' keys can be sent by the client, indicating that
  55          * the client is okay to speak any of them, select the greatest version
  56          * that the client has requested.  This is due to the assumption that
  57          * the most recent protocol version will be the most state-of-the-art.
  58          */
  59         if (git_protocol) {
  60                 struct string_list list = STRING_LIST_INIT_DUP;
  61                 const struct string_list_item *item;
  62                 string_list_split(&list, git_protocol, ':', -1);
  63
  64                 for_each_string_list_item(item, &list) {
  65                         const char *value;
  66                         enum protocol_version v;
  67
  68                         if (skip_prefix(item->string, "version=", &value)) {
  69                                 v = parse_protocol_version(value);
  70                                 if (v > version)
  71                                         version = v;
  72                         }
  73                 }
  74
  75                 string_list_clear(&list, 0);
  76         }
  77
  78         trace2_data_intmax("transfer", NULL, "negotiated-version", version);
  79
  80         return version;
  81 }
  82
  83 enum protocol_version determine_protocol_version_client(const char *server_response)
  84 {
  85         enum protocol_version version = protocol_v0;
  86
  87         if (skip_prefix(server_response, "version ", &server_response)) {
  88                 version = parse_protocol_version(server_response);
  89
  90                 if (version == protocol_unknown_version)
  91                         die("server is speaking an unknown protocol");
  92                 if (version == protocol_v0)
  93                         die("protocol error: server explicitly said version 0");
  94         }
  95
  96         return version;
  97 }