Merge branch 'jk/version-string'

Teaches git native protocol agents to show software version over the
wire.

* jk/version-string:
  http: get default user-agent from git_user_agent
  version: add git_user_agent function
  move git_version_string into version.c

Author: gitster

Makefile

@@ -296,6 +296,9 @@ all::
 # the diff algorithm.  It gives a nice speedup if your processor has
 # fast unaligned word loads.  Does NOT work on big-endian systems!
 # Enabled by default on x86_64.
+#
+# Define GIT_USER_AGENT if you want to change how git identifies itself during
+# network interactions.  The default is "git/$(GIT_VERSION)".
 
 GIT-VERSION-FILE: FORCE
 	@$(SHELL_PATH) ./GIT-VERSION-GEN
@@ -799,6 +802,7 @@ LIB_OBJS += usage.o
 LIB_OBJS += userdiff.o
 LIB_OBJS += utf8.o
 LIB_OBJS += varint.o
+LIB_OBJS += version.o
 LIB_OBJS += walker.o
 LIB_OBJS += wrapper.o
 LIB_OBJS += write_or_die.o
@@ -904,6 +908,8 @@ BUILTIN_OBJS += builtin/write-tree.o
 GITLIBS = $(LIB_FILE) $(XDIFF_LIB)
 EXTLIBS =
 
+GIT_USER_AGENT = git/$(GIT_VERSION)
+
 #
 # Platform specific tweaks
 #
@@ -1915,6 +1921,11 @@ SHELL_PATH_CQ_SQ = $(subst ','\'',$(SHELL_PATH_CQ))
 BASIC_CFLAGS += -DSHELL_PATH='$(SHELL_PATH_CQ_SQ)'
 endif
 
+GIT_USER_AGENT_SQ = $(subst ','\'',$(GIT_USER_AGENT))
+GIT_USER_AGENT_CQ = "$(subst ",\",$(subst \,\\,$(GIT_USER_AGENT)))"
+GIT_USER_AGENT_CQ_SQ = $(subst ','\'',$(GIT_USER_AGENT_CQ))
+BASIC_CFLAGS += -DGIT_USER_AGENT='$(GIT_USER_AGENT_CQ_SQ)'
+
 ALL_CFLAGS += $(BASIC_CFLAGS)
 ALL_LDFLAGS += $(BASIC_LDFLAGS)
 
@@ -1962,7 +1973,7 @@ strip: $(PROGRAMS) git$X
 	$(STRIP) $(STRIP_OPTS) $(PROGRAMS) git$X
 
 git.o: common-cmds.h
-git.sp git.s git.o: EXTRA_CPPFLAGS = -DGIT_VERSION='"$(GIT_VERSION)"' \
+git.sp git.s git.o: EXTRA_CPPFLAGS = \
 	'-DGIT_HTML_PATH="$(htmldir_SQ)"' \
 	'-DGIT_MAN_PATH="$(mandir_SQ)"' \
 	'-DGIT_INFO_PATH="$(infodir_SQ)"'
@@ -1979,6 +1990,9 @@ builtin/help.sp builtin/help.s builtin/help.o: EXTRA_CPPFLAGS = \
 	'-DGIT_MAN_PATH="$(mandir_SQ)"' \
 	'-DGIT_INFO_PATH="$(infodir_SQ)"'
 
+version.sp version.s version.o: EXTRA_CPPFLAGS = \
+	'-DGIT_VERSION="$(GIT_VERSION)"'
+
 $(BUILT_INS): git$X
 	$(QUIET_BUILT_IN)$(RM) $@ && \
 	ln git$X $@ 2>/dev/null || \
@@ -1996,6 +2010,7 @@ sed -e '1s|#!.*/sh|#!$(SHELL_PATH_SQ)|' \
     -e 's|@SHELL_PATH@|$(SHELL_PATH_SQ)|' \
     -e 's|@@DIFF@@|$(DIFF_SQ)|' \
     -e 's/@@GIT_VERSION@@/$(GIT_VERSION)/g' \
+    -e 's|@@GIT_USER_AGENT@@|$(GIT_USER_AGENT_SQ)|g' \
     -e 's|@@LOCALEDIR@@|$(localedir_SQ)|g' \
     -e 's/@@NO_CURL@@/$(NO_CURL)/g' \
     -e 's/@@USE_GETTEXT_SCHEME@@/$(USE_GETTEXT_SCHEME)/g' \
@@ -2089,7 +2104,7 @@ configure: configure.ac
 	$(RM) $<+
 
 # These can record GIT_VERSION
-git.o git.spec http.o \
+version.o git.spec \
 	$(patsubst %.sh,%,$(SCRIPT_SH)) \
 	$(patsubst %.perl,%,$(SCRIPT_PERL)) \
 	: GIT-VERSION-FILE
@@ -2259,9 +2274,6 @@ attr.sp attr.s attr.o: EXTRA_CPPFLAGS = \
 gettext.sp gettext.s gettext.o: EXTRA_CPPFLAGS = \
 	-DGIT_LOCALE_PATH='"$(localedir_SQ)"'
 
-http.sp http.s http.o: EXTRA_CPPFLAGS = \
-	-DGIT_HTTP_USER_AGENT='"git/$(GIT_VERSION)"'
-
 ifdef NO_EXPAT
 http-walker.sp http-walker.s http-walker.o: EXTRA_CPPFLAGS = -DNO_EXPAT
 endif

builtin.h

@@ -9,7 +9,6 @@
 
 #define DEFAULT_MERGE_LOG_LEN 20
 
-extern const char git_version_string[];
 extern const char git_usage_string[];
 extern const char git_more_info_string[];
 

builtin/log.c

@@ -21,6 +21,7 @@
 #include "parse-options.h"
 #include "branch.h"
 #include "streaming.h"
+#include "version.h"
 
 /* Set a default date-time format for git log ("log.date" config variable) */
 static const char *default_date_mode = NULL;

git.c

@@ -256,8 +256,6 @@ static int handle_alias(int *argcp, const char ***argv)
 	return ret;
 }
 
-const char git_version_string[] = GIT_VERSION;
-
 #define RUN_SETUP		(1<<0)
 #define RUN_SETUP_GENTLY	(1<<1)
 #define USE_PAGER		(1<<2)

help.c

@@ -6,6 +6,7 @@
 #include "common-cmds.h"
 #include "string-list.h"
 #include "column.h"
+#include "version.h"
 
 void add_cmdname(struct cmdnames *cmds, const char *name, int len)
 {

http.c

@@ -4,6 +4,7 @@
 #include "run-command.h"
 #include "url.h"
 #include "credential.h"
+#include "version.h"
 
 int active_requests;
 int http_is_verbose;
@@ -299,7 +300,7 @@ static CURL *get_curl_handle(void)
 		curl_easy_setopt(result, CURLOPT_VERBOSE, 1);
 
 	curl_easy_setopt(result, CURLOPT_USERAGENT,
-		user_agent ? user_agent : GIT_HTTP_USER_AGENT);
+		user_agent ? user_agent : git_user_agent());
 
 	if (curl_ftp_no_epsv)
 		curl_easy_setopt(result, CURLOPT_FTP_USE_EPSV, 0);

version.c

@@ -0,0 +1,17 @@
+#include "git-compat-util.h"
+#include "version.h"
+
+const char git_version_string[] = GIT_VERSION;
+
+const char *git_user_agent(void)
+{
+	static const char *agent = NULL;
+
+	if (!agent) {
+		agent = getenv("GIT_USER_AGENT");
+		if (!agent)
+			agent = GIT_USER_AGENT;
+	}
+
+	return agent;
+}

version.h

@@ -0,0 +1,8 @@
+#ifndef VERSION_H
+#define VERSION_H
+
+extern const char git_version_string[];
+
+const char *git_user_agent(void);
+
+#endif /* VERSION_H */