[PATCH 2/3] add basic lua infrastructure
- From
Jeff King <peff@peff.net>
- Date
- Sep 25, 2012, 00:25 UTC
- Message-ID
- <20120925002511.GB19605@sigill.intra.peff.net>
- In-Reply-To
- <20120925002325.GA19560@sigill.intra.peff.net>
This adds a small module for examining parts of a commit from inside a lua interpreter. Eventually you'll be able to do grep-like filtering and --pretty formatting.
The most naive presentation would be to parse the whole commit and put it in a lua table. However, instead we build upon the incremental parsing used by the --format parser, and lazily parse bits of the commit as the lua code requests them.
Signed-off-by: Jeff King <peff@peff.net> --- Set "USE_LUA" in your Makefile to turn it on.
Makefile | 7 +++ lua-commit.c | 166 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ lua-commit.h | 9 ++++ 3 files changed, 182 insertions(+) create mode 100644 lua-commit.c create mode 100644 lua-commit.h
diff --git a/Makefile b/Makefile index a49d1db..54473e2 100644 --- a/Makefile +++ b/Makefile @@ -636,6 +636,7 @@ LIB_H += log-tree.h LIB_H += list-objects.h LIB_H += ll-merge.h LIB_H += log-tree.h +LIB_H += lua-commit.h LIB_H += mailmap.h LIB_H += merge-file.h LIB_H += merge-recursive.h @@ -749,6 +750,7 @@ LIB_OBJS += log-tree.o LIB_OBJS += ll-merge.o LIB_OBJS += lockfile.o LIB_OBJS += log-tree.o +LIB_OBJS += lua-commit.o LIB_OBJS += mailmap.o LIB_OBJS += match-trees.o LIB_OBJS += merge-file.o @@ -1818,6 +1820,11 @@ endif COMPAT_OBJS += compat/nedmalloc/nedmalloc.o endif +ifdef USE_LUA + BASIC_CFLAGS += -DUSE_LUA `pkg-config --cflags lua5.2` + EXTLIBS += `pkg-config --libs lua5.2` +endif + ifdef GIT_TEST_CMP_USE_COPIED_CONTEXT export GIT_TEST_CMP_USE_COPIED_CONTEXT endif diff --git a/lua-commit.c b/lua-commit.c new file mode 100644 index 0000000..ce1eeeb --- /dev/null +++ b/lua-commit.c @@ -0,0 +1,166 @@ +#include "cache.h" +#include "lua-commit.h" +#include "commit.h" + +#ifndef USE_LUA + +static const char msg[] = "git was built without lua support"; + +void lua_commit_init(const char *) +{ + die(msg); +} + +void lua_commit_format(struct strbuf *, + struct format_commit_context *) +{ + die(msg); +} + +#else + +#include <lua.h> +#include <lauxlib.h> +#include <lualib.h> + +static lua_State *lua; + +/* XXX + * We need to access this from functions called from inside lua. Probably it + * would be cleaner use a lua "register" to let each function access it, but I + * haven't looked into it. + */ +static struct format_commit_context *c; + +static int lua_fun_hash(lua_State *lua) +{ + lua_pushstring(lua, sha1_to_hex(c->commit->object.sha1)); + return 1; +} + +static int lua_fun_abbrev(lua_State *lua) +{ + const char *hex; + unsigned char sha1[20]; + + hex = lua_tostring(lua, -1); + if (!hex || get_sha1_hex(hex, sha1)) { + lua_pushstring(lua, "abbrev requires a sha1"); + lua_error(lua); + } + + lua_pushstring(lua, find_unique_abbrev(sha1, c->pretty_ctx->abbrev)); + return 1; +} + +static int get_ident(lua_State *lua, const char *line, int len) +{ + struct ident_split s; + + if (split_ident_line(&s, line, len) < 0) { + lua_pushstring(lua, "unable to parse ident line"); + lua_error(lua); + } + + lua_createtable(lua, 0, 2); + lua_pushstring(lua, "name"); + lua_pushlstring(lua, s.name_begin, s.name_end - s.name_begin); + lua_settable(lua, -3); + lua_pushstring(lua, "email"); + lua_pushlstring(lua, s.mail_begin, s.mail_end - s.mail_begin); + lua_settable(lua, -3); + + /* XXX should also put date in the table */ + + return 1; +} + +static int lua_fun_author(lua_State *lua) +{ + if (!c->commit_header_parsed) + parse_commit_header(c); + return get_ident(lua, c->message + c->author.off, c->author.len); +} + +static int lua_fun_committer(lua_State *lua) +{ + if (!c->commit_header_parsed) + parse_commit_header(c); + return get_ident(lua, c->message + c->committer.off, c->committer.len); +} + +static int lua_fun_message(lua_State *lua) +{ + lua_pushstring(lua, c->message + c->message_off + 1); + return 1; +} + +static int lua_fun_subject(lua_State *lua) +{ + struct strbuf tmp = STRBUF_INIT; + + if (!c->commit_header_parsed) + parse_commit_header(c); + if (!c->commit_message_parsed) + parse_commit_message(c); + + format_subject(&tmp, c->message + c->subject_off, " "); + lua_pushlstring(lua, tmp.buf, tmp.len); + return 1; +} + +static int lua_fun_body(lua_State *lua) +{ + if (!c->commit_header_parsed) + parse_commit_header(c); + if (!c->commit_message_parsed) + parse_commit_message(c); + + lua_pushstring(lua, c->message + c->body_off); + return 1; +} + +void lua_commit_init(const char *snippet) +{ + if (!lua) { + lua = luaL_newstate(); + if (!lua) + die("unable to open lua interpreter"); + luaL_openlibs(lua); + +#define REG(name) do { \ + lua_pushcfunction(lua, lua_fun_##name); \ + lua_setglobal(lua, #name); \ +} while(0) + + REG(hash); + REG(abbrev); + REG(author); + REG(committer); + REG(message); + REG(subject); + REG(body); + } + + if (luaL_loadstring(lua, snippet)) + die("unable to load lua snippet: %s", snippet); +} + +void lua_commit_format(struct strbuf *out, + struct format_commit_context *context) +{ + const char *ret; + size_t len; + + c = context; + + lua_pushvalue(lua, -1); + if (lua_pcall(lua, 0, 1, 0)) + die("lua failed: %s", lua_tostring(lua, -1)); + + ret = lua_tolstring(lua, -1, &len); + strbuf_add(out, ret, len); + lua_pop(lua, 1); +} + +#endif /* USE_LUA */ diff --git a/lua-commit.h b/lua-commit.h new file mode 100644 index 0000000..aaffced --- /dev/null +++ b/lua-commit.h @@ -0,0 +1,9 @@ +#ifndef LUA_COMMIT_H +#define LUA_COMMIT_H + +struct format_commit_context; + +void lua_commit_init(const char *snippet); +void lua_commit_format(struct strbuf *out, struct format_commit_context *context); + +#endif
-- 1.7.12.1.10.g6537447