diff options
Diffstat (limited to '')
| -rw-r--r-- | src/hlua.c | 219 |
1 files changed, 183 insertions, 36 deletions
@@ -260,6 +260,70 @@ static const char *hlua_tostring_safe(lua_State *L, int index) return str; } +/* below is an helper function similar to lua_pushvfstring() to push a + * formatted string on Lua stack but in a safe way (function may not LJMP). + * It can be useful to push allocated strings (ie: error messages) on the + * stack and ensure proper cleanup. + * + * Returns a pointer to the internal copy of the string on success and NULL + * on error. + * + * It is assumed that the calling function is allowed to manipulate <L> + */ +__LJMP static int _hlua_pushvfstring_safe(lua_State *L) +{ + const char **dst = lua_touserdata(L, 1); + const char *fmt = lua_touserdata(L, 2); + va_list *argp = lua_touserdata(L, 3); + + *dst = lua_pushvfstring(L, fmt, *argp); + return 1; +} +static const char *hlua_pushvfstring_safe(lua_State *L, const char *fmt, va_list argp) +{ + const char *dst = NULL; + va_list cpy_argp; /* required if argp is implemented as array type */ + + if (!lua_checkstack(L, 4)) + return NULL; + + va_copy(cpy_argp, argp); + + /* push our custom _hlua_pushvfstring_safe() function on the stack, then + * push our destination string pointer, fmt and arg list + */ + lua_pushcfunction(L, _hlua_pushvfstring_safe); + lua_pushlightuserdata(L, &dst); // 1st func argument = dst string pointer + lua_pushlightuserdata(L, (void *)fmt); // 2nd func argument = fmt + lua_pushlightuserdata(L, &cpy_argp); // 3rd func argument = arg list + + /* call our custom function with proper arguments using pcall() to catch + * exceptions (if any) + */ + switch (lua_pcall(L, 3, 1, 0)) { + case LUA_OK: + break; + default: + /* error was caught */ + dst = NULL; + } + va_end(cpy_argp); + + return dst; +} + +static const char *hlua_pushfstring_safe(lua_State *L, const char *fmt, ...) +{ + va_list argp; + const char *dst; + + va_start(argp, fmt); + dst = hlua_pushvfstring_safe(L, fmt, argp); + va_end(argp); + + return dst; +} + #define SET_SAFE_LJMP_L(__L, __HLUA) \ ({ \ int ret; \ @@ -784,20 +848,41 @@ void hlua_unref(lua_State *L, int ref) luaL_unref(L, LUA_REGISTRYINDEX, ref); } -__LJMP const char *hlua_traceback(lua_State *L, const char* sep) +__LJMP static int _hlua_traceback(lua_State *L) +{ + lua_Debug *ar = lua_touserdata(L, 1); + + /* Fill fields: + * 'S': fills in the fields source, short_src, linedefined, lastlinedefined, and what; + * 'l': fills in the field currentline; + * 'n': fills in the field name and namewhat; + * 't': fills in the field istailcall; + */ + return lua_getinfo(L, "Slnt", ar); +} + + +/* This function cannot fail (output will simply be truncated upon errors) */ +const char *hlua_traceback(lua_State *L, const char* sep) { lua_Debug ar; int level = 0; struct buffer *msg = get_trash_chunk(); while (lua_getstack(L, level++, &ar)) { - /* Fill fields: - * 'S': fills in the fields source, short_src, linedefined, lastlinedefined, and what; - * 'l': fills in the field currentline; - * 'n': fills in the field name and namewhat; - * 't': fills in the field istailcall; - */ - lua_getinfo(L, "Slnt", &ar); + if (!lua_checkstack(L, 2)) + goto end; // abort + + lua_pushcfunction(L, _hlua_traceback); + lua_pushlightuserdata(L, &ar); + + /* safe getinfo */ + switch (lua_pcall(L, 1, 1, 0)) { + case LUA_OK: + break; + default: + goto end; // abort + } /* skip these empty entries, usually they come from deep C functions */ if (ar.currentline < 0 && *ar.what == 'C' && !*ar.namewhat && !ar.name) @@ -838,6 +923,7 @@ __LJMP const char *hlua_traceback(lua_State *L, const char* sep) chunk_appendf(msg, " ..."); } + end: return msg->area; } @@ -855,16 +941,50 @@ __LJMP static inline void check_args(lua_State *L, int nb, char *fcn) /* This function pushes an error string prefixed by the file name * and the line number where the error is encountered. + * + * It returns 1 on success and 0 on failure (function won't LJMP) */ +__LJMP static int _hlua_pusherror(lua_State *L) +{ + const char *fmt = lua_touserdata(L, 1); + va_list *argp = lua_touserdata(L, 2); + + luaL_where(L, 2); + lua_pushvfstring(L, fmt, *argp); + lua_concat(L, 2); + + return 1; +} static int hlua_pusherror(lua_State *L, const char *fmt, ...) { va_list argp; + int ret = 1; + + if (!lua_checkstack(L, 3)) + return 0; + va_start(argp, fmt); - luaL_where(L, 1); - lua_pushvfstring(L, fmt, argp); + + /* push our custom _hlua_pusherror() function on the stack, then + * push fmt and arg list + */ + lua_pushcfunction(L, _hlua_pusherror); + lua_pushlightuserdata(L, (void *)fmt); // 1st func argument = fmt + lua_pushlightuserdata(L, &argp); // 2nd func argument = arg list + + /* call our custom function with proper arguments using pcall() to catch + * exceptions (if any) + */ + switch (lua_pcall(L, 2, 1, 0)) { + case LUA_OK: + break; + default: + ret = 0; + } + va_end(argp); - lua_concat(L, 2); - return 1; + + return ret; } /* This functions is used with sample fetch and converters. It @@ -1367,8 +1487,8 @@ __LJMP int hlua_lua2arg_check(lua_State *L, int first, struct arg *argp, } reg = regex_comp(argp[idx].data.str.area, !(argp[idx].type_flags & ARGF_REG_ICASE), 1, &err); if (!reg) { - msg = lua_pushfstring(L, "error compiling regex '%s' : '%s'", - argp[idx].data.str.area, err); + msg = hlua_pushfstring_safe(L, "error compiling regex '%s' : '%s'", + argp[idx].data.str.area, err); free(err); goto error; } @@ -1388,7 +1508,8 @@ __LJMP int hlua_lua2arg_check(lua_State *L, int first, struct arg *argp, ul = auth_find_userlist(argp[idx].data.str.area); if (!ul) { - msg = lua_pushfstring(L, "unable to find userlist '%s'", argp[idx].data.str.area); + msg = hlua_pushfstring_safe(L, "unable to find userlist '%s'", + argp[idx].data.str.area); goto error; } argp[idx].type = ARGT_USR; @@ -1412,9 +1533,9 @@ __LJMP int hlua_lua2arg_check(lua_State *L, int first, struct arg *argp, /* Check for type of argument. */ if ((mask & ARGT_MASK) != argp[idx].type) { - msg = lua_pushfstring(L, "'%s' expected, got '%s'", - arg_type_names[(mask & ARGT_MASK)], - arg_type_names[argp[idx].type & ARGT_MASK]); + msg = hlua_pushfstring_safe(L, "'%s' expected, got '%s'", + arg_type_names[(mask & ARGT_MASK)], + arg_type_names[argp[idx].type & ARGT_MASK]); goto error; } @@ -1960,12 +2081,14 @@ resume_execution: msg = hlua_tostring_safe(lua->T, -1); trace = hlua_traceback(lua->T, ", "); if (msg) - lua_pushfstring(lua->T, "[state-id %d] runtime error: %s from %s", lua->state_id, msg, trace); + hlua_pushfstring_safe(lua->T, "[state-id %d] runtime error: %s from %s", + lua->state_id, msg, trace); else - lua_pushfstring(lua->T, "[state-id %d] unknown runtime error from %s", lua->state_id, trace); + hlua_pushfstring_safe(lua->T, "[state-id %d] unknown runtime error from %s", + lua->state_id, trace); - /* Move the error msg at the top and then empty the stack except last msg */ - lua_insert(lua->T, -lua_gettop(lua->T)); + /* Move the error msg at the bottom and then empty the stack except last msg */ + lua_insert(lua->T, 1); lua_settop(lua->T, 1); ret = HLUA_E_ERRMSG; break; @@ -1984,12 +2107,14 @@ resume_execution: } msg = hlua_tostring_safe(lua->T, -1); if (msg) - lua_pushfstring(lua->T, "[state-id %d] message handler error: %s", lua->state_id, msg); + hlua_pushfstring_safe(lua->T, "[state-id %d] message handler error: %s", + lua->state_id, msg); else - lua_pushfstring(lua->T, "[state-id %d] message handler error", lua->state_id); + hlua_pushfstring_safe(lua->T, "[state-id %d] message handler error", + lua->state_id); - /* Move the error msg at the top and then empty the stack except last msg */ - lua_insert(lua->T, -lua_gettop(lua->T)); + /* Move the error msg at the bottom and then empty the stack except last msg */ + lua_insert(lua->T, 1); lua_settop(lua->T, 1); ret = HLUA_E_ERRMSG; break; @@ -2369,9 +2494,7 @@ __LJMP static int hlua_map_new(struct lua_State *L) /* error case: we can't use luaL_error because we must * free the err variable. */ - luaL_where(L, 1); - lua_pushfstring(L, "'new': %s.", err); - lua_concat(L, 2); + hlua_pusherror(L, "'new': %s.", err); free(err); chunk_destroy(&args[0].data.str); WILL_LJMP(lua_error(L)); @@ -4702,7 +4825,7 @@ __LJMP static int hlua_run_sample_fetch(lua_State *L) /* Run the special args checker. */ if (f->val_args && !f->val_args(args, NULL)) { - lua_pushfstring(L, "error in arguments"); + hlua_pushfstring_safe(L, "error in arguments"); goto error; } @@ -12989,8 +13112,10 @@ __LJMP static int hlua_ckch_commit_yield(lua_State *L, int status, lua_KContext list_for_each_entry_from(ckchi, &old_ckchs->ckch_inst, by_ckchs) { struct ckch_inst *new_inst; - /* it takes a lot of CPU to creates SSL_CTXs, so we yield every 10 CKCH instances */ - if (y % 10 == 0) { + /* it takes a lot of CPU to creates SSL_CTXs, so we yield every 10 CKCH instances + * during runtime + */ + if (hlua && (y % 10) == 0) { *lua_ckchi = ckchi; @@ -13018,8 +13143,9 @@ __LJMP static int hlua_ckch_commit_yield(lua_State *L, int status, lua_KContext error: ckch_store_free(new_ckchs); HA_SPIN_UNLOCK(CKCH_LOCK, &ckch_lock); - WILL_LJMP(luaL_error(L, "%s", err)); + hlua_pushfstring_safe(L, "%s", err); free(err); + WILL_LJMP(lua_error(L)); return 0; } @@ -13053,6 +13179,14 @@ __LJMP static int hlua_ckch_set(lua_State *L) WILL_LJMP(luaL_error(L, "'CertCache.set' needs a table as argument")); hlua = hlua_gethlua(L); + if (hlua && HLUA_CANT_YIELD(hlua)) { + /* using hlua_ckch_set() during runtime from a context that + * doesn't allow yielding (e.g.: fetches) is not supported + * as it may cause contention. + */ + WILL_LJMP(luaL_error(L, "Cannot use CertCache.set from a " + "non-yield capable runtime context")); + } /* FIXME: this should not return an error but should come back later */ if (HA_SPIN_TRYLOCK(CKCH_LOCK, &ckch_lock)) @@ -13135,15 +13269,28 @@ __LJMP static int hlua_ckch_set(lua_State *L) lua_ckchi = lua_newuserdata(L, sizeof(struct ckch_inst *)); *lua_ckchi = NULL; - task_wakeup(hlua->task, TASK_WOKEN_MSG); - MAY_LJMP(hlua_yieldk(L, 0, 0, hlua_ckch_commit_yield, TICK_ETERNITY, 0)); + if (hlua) { + /* yield right away to let hlua_ckch_commit_yield() benefit from + * a fresh task cycle on next wakeup + */ + task_wakeup(hlua->task, TASK_WOKEN_MSG); + MAY_LJMP(hlua_yieldk(L, 0, 0, hlua_ckch_commit_yield, TICK_ETERNITY, 0)); + } else { + /* body/init context: yielding not available, perform the commit as a + * 1-shot operation (may be slow, but haproxy process is starting so + * it is acceptable) + */ + hlua_ckch_commit_yield(L, LUA_OK, 0); + } end: HA_SPIN_UNLOCK(CKCH_LOCK, &ckch_lock); if (errcode & ERR_CODE) { ckch_store_free(new_ckchs); - WILL_LJMP(luaL_error(L, "%s", err)); + hlua_pushfstring_safe(L, "%s", err); + free(err); + WILL_LJMP(lua_error(L)); } free(err); |