Instead of having the client advertise a particular version number in the git protocol, we have managed extensions and backwards compatibility by having clients and servers advertise capabilities that they support. This is far more robust than having each side consult a table of known versions, and provides sufficient information for the protocol interaction to complete. However, it does not allow servers to keep statistics on which client versions are being used. This information is not necessary to complete the network request (the capabilities provide enough information for that), but it may be helpful to conduct a general survey of client versions in use. We already send the client version in the user-agent header for http requests; adding it here allows us to gather similar statistics for non-http requests. Signed-off-by: Jeff King <peff@xxxxxxxx> --- Two important changes from the previous round: 1. We sanitize the agent string to remove non-printable characters and whitespace (they are replaced with '.'). This generally shouldn't happen, but is a defensive measure against breaking the protocol. 2. The server half of the connection will advertise their versions in the capability strings, too. builtin/fetch-pack.c | 2 ++ builtin/receive-pack.c | 6 ++++-- builtin/send-pack.c | 7 +++++-- upload-pack.c | 7 +++++-- version.c | 21 +++++++++++++++++++++ version.h | 1 + 6 files changed, 38 insertions(+), 6 deletions(-) diff --git a/builtin/fetch-pack.c b/builtin/fetch-pack.c index 149db88..fe56596 100644 --- a/builtin/fetch-pack.c +++ b/builtin/fetch-pack.c @@ -10,6 +10,7 @@ #include "remote.h" #include "run-command.h" #include "transport.h" +#include "version.h" static int transfer_unpack_limit = -1; static int fetch_unpack_limit = -1; @@ -327,6 +328,7 @@ static int find_common(int fd[2], unsigned char *result_sha1, if (args.no_progress) strbuf_addstr(&c, " no-progress"); if (args.include_tag) strbuf_addstr(&c, " include-tag"); if (prefer_ofs_delta) strbuf_addstr(&c, " ofs-delta"); + strbuf_addf(&c, " agent=%s", git_user_agent_sanitized()); packet_buf_write(&req_buf, "want %s%s\n", remote_hex, c.buf); strbuf_release(&c); } else diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c index 0afb8b2..fbfa128 100644 --- a/builtin/receive-pack.c +++ b/builtin/receive-pack.c @@ -12,6 +12,7 @@ #include "string-list.h" #include "sha1-array.h" #include "connected.h" +#include "version.h" static const char receive_pack_usage[] = "git receive-pack <git-dir>"; @@ -121,10 +122,11 @@ static void show_ref(const char *path, const unsigned char *sha1) if (sent_capabilities) packet_write(1, "%s %s\n", sha1_to_hex(sha1), path); else - packet_write(1, "%s %s%c%s%s\n", + packet_write(1, "%s %s%c%s%s agent=%s\n", sha1_to_hex(sha1), path, 0, " report-status delete-refs side-band-64k quiet", - prefer_ofs_delta ? " ofs-delta" : ""); + prefer_ofs_delta ? " ofs-delta" : "", + git_user_agent_sanitized()); sent_capabilities = 1; } diff --git a/builtin/send-pack.c b/builtin/send-pack.c index d5d7105..c4d4211 100644 --- a/builtin/send-pack.c +++ b/builtin/send-pack.c @@ -8,6 +8,7 @@ #include "send-pack.h" #include "quote.h" #include "transport.h" +#include "version.h" static const char send_pack_usage[] = "git send-pack [--all | --mirror] [--dry-run] [--force] [--receive-pack=<git-receive-pack>] [--verbose] [--thin] [<host>:]<directory> [<ref>...]\n" @@ -306,11 +307,13 @@ int send_pack(struct send_pack_args *args, int quiet = quiet_supported && (args->quiet || !args->progress); if (!cmds_sent && (status_report || use_sideband || args->quiet)) { - packet_buf_write(&req_buf, "%s %s %s%c%s%s%s", + packet_buf_write(&req_buf, + "%s %s %s%c%s%s%s agent=%s", old_hex, new_hex, ref->name, 0, status_report ? " report-status" : "", use_sideband ? " side-band-64k" : "", - quiet ? " quiet" : ""); + quiet ? " quiet" : "", + git_user_agent_sanitized()); } else packet_buf_write(&req_buf, "%s %s %s", diff --git a/upload-pack.c b/upload-pack.c index bb08e2e..2e90ccb 100644 --- a/upload-pack.c +++ b/upload-pack.c @@ -11,6 +11,7 @@ #include "list-objects.h" #include "run-command.h" #include "sigchain.h" +#include "version.h" static const char upload_pack_usage[] = "git upload-pack [--strict] [--timeout=<n>] <dir>"; @@ -734,9 +735,11 @@ static int send_ref(const char *refname, const unsigned char *sha1, int flag, vo } if (capabilities) - packet_write(1, "%s %s%c%s%s\n", sha1_to_hex(sha1), refname_nons, + packet_write(1, "%s %s%c%s%s agent=%s\n", + sha1_to_hex(sha1), refname_nons, 0, capabilities, - stateless_rpc ? " no-done" : ""); + stateless_rpc ? " no-done" : "", + git_user_agent_sanitized()); else packet_write(1, "%s %s\n", sha1_to_hex(sha1), refname_nons); capabilities = NULL; diff --git a/version.c b/version.c index f98d5a6..6106a80 100644 --- a/version.c +++ b/version.c @@ -1,5 +1,6 @@ #include "git-compat-util.h" #include "version.h" +#include "strbuf.h" const char git_version_string[] = GIT_VERSION; @@ -15,3 +16,23 @@ const char *git_user_agent(void) return agent; } + +const char *git_user_agent_sanitized(void) +{ + static const char *agent = NULL; + + if (!agent) { + struct strbuf buf = STRBUF_INIT; + int i; + + strbuf_addstr(&buf, git_user_agent()); + strbuf_trim(&buf); + for (i = 0; i < buf.len; i++) { + if (buf.buf[i] <= 32 || buf.buf[i] >= 127) + buf.buf[i] = '.'; + } + agent = buf.buf; + } + + return agent; +} diff --git a/version.h b/version.h index fd9cdd6..6911a4f 100644 --- a/version.h +++ b/version.h @@ -4,5 +4,6 @@ extern const char git_version_string[]; const char *git_user_agent(void); +const char *git_user_agent_sanitized(void); #endif /* VERSION_H */ -- 1.7.7.7.32.g4b73117 -- To unsubscribe from this list: send the line "unsubscribe git" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html