diff options
author | Clement Farabet <cfarabet@twitter.com> | 2014-12-25 20:49:39 +0300 |
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committer | Clement Farabet <cfarabet@twitter.com> | 2014-12-25 20:49:39 +0300 |
commit | 396db0f71e96dd66983fcca8b7461f0e452dc7dd (patch) | |
tree | 1a57f8de20a9ecfa857beab94e3ad951d4751e75 /readline.c | |
parent | 64f19ae831cf9690a71886e78b3976b7e8844144 (diff) |
Total revamp of readline support.
(now using plain C bindings to readline)
Diffstat (limited to 'readline.c')
-rw-r--r-- | readline.c | 294 |
1 files changed, 294 insertions, 0 deletions
diff --git a/readline.c b/readline.c new file mode 100644 index 0000000..9edbef2 --- /dev/null +++ b/readline.c @@ -0,0 +1,294 @@ +// Bindings to readline +#include <stdlib.h> +#include <string.h> +#include "lua.h" +#include "lauxlib.h" +#include "lualib.h" +#include <readline/readline.h> +#include <readline/history.h> + +/* +** Lua 5.1.4 advanced readline support for the GNU readline and history +** libraries or compatible replacements. +** +** Author: Mike Pall. +** Maintainer: Sean Bolton (sean at smbolton dot com). +** +** Copyright (C) 2004-2006, 2011 Mike Pall. Same license as Lua. See lua.h. +** +** Advanced features: +** - Completion of keywords and global variable names. +** - Recursive and metatable-aware completion of variable names. +** - Context sensitive delimiter completion. +** - Save/restore of the history to/from a file (LUA_HISTORY env variable). +** - Setting a limit for the size of the history (LUA_HISTSIZE env variable). +** - Setting the app name to allow for $if lua ... $endif in ~/.inputrc. +** +** Start lua and try these (replace ~ with the TAB key): +** +** ~~ +** fu~foo() ret~fa~end<CR> +** io~~~s~~~o~~~w~"foo\n")<CR> +** +** The ~~ are just for demonstration purposes (io~s~o~w~ suffices, of course). +** +** If you are used to zsh/tcsh-style completion support, try adding +** 'TAB: menu-complete' and 'C-d: possible-completions' to your ~/.inputrc. +** +** The patch has been successfully tested with: +** +** GNU readline 2.2.1 (1998-07-17) +** GNU readline 4.0 (1999-02-18) [harmless compiler warning] +** GNU readline 4.3 (2002-07-16) +** GNU readline 5.0 (2004-07-27) +** GNU readline 5.1 (2005-12-07) +** GNU readline 5.2 (2006-10-11) +** GNU readline 6.0 (2009-02-20) +** GNU readline 6.2 (2011-02-13) +** MacOSX libedit 2.11 (2008-07-12) +** NETBSD libedit 2.6.5 (2002-03-25) +** NETBSD libedit 2.6.9 (2004-05-01) +** +** Change Log: +** 2004-2006 Mike Pall - original patch +** 2009/08/24 Sean Bolton - updated for GNU readline version 6 +** 2011/12/14 Sean Bolton - fixed segfault when using Mac OS X libedit 2.11 +*/ + +static char *lua_rl_hist; +static int lua_rl_histsize; + +static lua_State *lua_rl_L; /* User data is not passed to rl callbacks. */ + +/* Reserved keywords. */ +static const char *const lua_rl_keywords[] = { + "and", "break", "do", "else", "elseif", "end", "false", + "for", "function", "if", "in", "local", "nil", "not", "or", + "repeat", "return", "then", "true", "until", "while", NULL +}; + +static int valididentifier(const char *s) +{ + if (!(isalpha(*s) || *s == '_')) return 0; + for (s++; *s; s++) if (!(isalpha(*s) || isdigit(*s) || *s == '_')) return 0; + return 1; +} + +/* Dynamically resizable match list. */ +typedef struct { + char **list; + size_t idx, allocated, matchlen; +} dmlist; + +/* Add prefix + string + suffix to list and compute common prefix. */ +static int lua_rl_dmadd(dmlist *ml, const char *p, size_t pn, const char *s, + int suf) +{ + char *t = NULL; + + if (ml->idx+1 >= ml->allocated && + !(ml->list = realloc(ml->list, sizeof(char *)*(ml->allocated += 32)))) + return -1; + + if (s) { + size_t n = strlen(s); + if (!(t = (char *)malloc(sizeof(char)*(pn+n+(suf?2:1))))) return 1; + memcpy(t, p, pn); + memcpy(t+pn, s, n); + n += pn; + t[n] = suf; + if (suf) t[++n] = '\0'; + + if (ml->idx == 0) { + ml->matchlen = n; + } else { + size_t i; + for (i = 0; i < ml->matchlen && i < n && ml->list[1][i] == t[i]; i++) ; + ml->matchlen = i; /* Set matchlen to common prefix. */ + } + } + + ml->list[++ml->idx] = t; + return 0; +} + +/* Get __index field of metatable of object on top of stack. */ +static int lua_rl_getmetaindex(lua_State *L) +{ + if (!lua_getmetatable(L, -1)) { lua_pop(L, 1); return 0; } + + /* prefer __metatable if it exists */ + lua_pushstring(L, "__metatable"); + lua_rawget(L, -2); + if(lua_istable(L, -1)) + { + lua_remove(L, -2); + return 1; + } + else + lua_pop(L, 1); + + lua_pushstring(L, "__index"); + lua_rawget(L, -2); + lua_replace(L, -2); + if (lua_isnil(L, -1) || lua_rawequal(L, -1, -2)) { lua_pop(L, 2); return 0; } + lua_replace(L, -2); + return 1; +} /* 1: obj -- val, 0: obj -- */ + +/* Get field from object on top of stack. Avoid calling metamethods. */ +static int lua_rl_getfield(lua_State *L, const char *s, size_t n) +{ + int i = 20; /* Avoid infinite metatable loops. */ + do { + if (lua_istable(L, -1)) { + lua_pushlstring(L, s, n); + lua_rawget(L, -2); + if (!lua_isnil(L, -1)) { lua_replace(L, -2); return 1; } + lua_pop(L, 1); + } + } while (--i > 0 && lua_rl_getmetaindex(L)); + lua_pop(L, 1); + return 0; +} /* 1: obj -- val, 0: obj -- */ + +/* Completion callback. */ +static char **lua_rl_complete(const char *text, int start, int end) +{ + lua_State *L = lua_rl_L; + dmlist ml; + const char *s; + size_t i, n, dot, loop; + int savetop; + + if (!(text[0] == '\0' || isalpha(text[0]) || text[0] == '_')) return NULL; + + ml.list = NULL; + ml.idx = ml.allocated = ml.matchlen = 0; + + savetop = lua_gettop(L); + lua_pushvalue(L, LUA_GLOBALSINDEX); + for (n = (size_t)(end-start), i = dot = 0; i < n; i++) + if (text[i] == '.' || text[i] == ':') { + if (!lua_rl_getfield(L, text+dot, i-dot)) + goto error; /* Invalid prefix. */ + dot = i+1; /* Points to first char after dot/colon. */ + } + + /* Add all matches against keywords if there is no dot/colon. */ + if (dot == 0) + for (i = 0; (s = lua_rl_keywords[i]) != NULL; i++) + if (!strncmp(s, text, n) && lua_rl_dmadd(&ml, NULL, 0, s, ' ')) + goto error; + + /* Add all valid matches from all tables/metatables. */ + loop = 0; /* Avoid infinite metatable loops. */ + do { + if (lua_istable(L, -1) && + (loop == 0 || !lua_rawequal(L, -1, LUA_GLOBALSINDEX))) + for (lua_pushnil(L); lua_next(L, -2); lua_pop(L, 1)) + if (lua_type(L, -2) == LUA_TSTRING) { + s = lua_tostring(L, -2); + /* Only match names starting with '_' if explicitly requested. */ + if (!strncmp(s, text+dot, n-dot) && valididentifier(s) && + (*s != '_' || text[dot] == '_')) { + int suf = ' '; /* Default suffix is a space. */ + switch (lua_type(L, -1)) { + case LUA_TTABLE: suf = '.'; break; /* No way to guess ':'. */ + case LUA_TFUNCTION: suf = '('; break; + case LUA_TUSERDATA: + if (lua_getmetatable(L, -1)) { lua_pop(L, 1); suf = ':'; } + break; + } + if (lua_rl_dmadd(&ml, text, dot, s, suf)) goto error; + } + } + } while (++loop < 20 && lua_rl_getmetaindex(L)); + + if (ml.idx == 0) { +error: + lua_settop(L, savetop); + return NULL; + } else { + /* list[0] holds the common prefix of all matches (may be ""). */ + /* If there is only one match, list[0] and list[1] will be the same. */ + if (!(ml.list[0] = (char *)malloc(sizeof(char)*(ml.matchlen+1)))) + goto error; + memcpy(ml.list[0], ml.list[1], ml.matchlen); + ml.list[0][ml.matchlen] = '\0'; + /* Add the NULL list terminator. */ + if (lua_rl_dmadd(&ml, NULL, 0, NULL, 0)) goto error; + } + + lua_settop(L, savetop); +#if RL_READLINE_VERSION >= 0x0600 + rl_completion_suppress_append = 1; +#endif + return ml.list; +} + +/* Initialize readline library. */ +static int f_setup(lua_State *L) +{ + char *s; + + lua_rl_L = L; + + /* This allows for $if lua ... $endif in ~/.inputrc. */ + rl_readline_name = "lua"; + /* Break words at every non-identifier character except '.' and ':'. */ + rl_completer_word_break_characters = + "\t\r\n !\"#$%&'()*+,-/;<=>?@[\\]^`{|}~"; + rl_completer_quote_characters = "\"'"; +/* #if RL_READLINE_VERSION < 0x0600 */ + rl_completion_append_character = '\0'; +/* #endif */ + rl_attempted_completion_function = lua_rl_complete; + rl_initialize(); + + return 0; +} + +static int f_readline(lua_State* L) +{ + const char* prompt = lua_tostring(L,1); + const char* line = readline(prompt); + lua_pushstring(L,line); + free((void *)line); // Lua makes a copy... + return 1; +} + +static int f_add_history(lua_State* L) +{ + if (lua_strlen(L,1) > 0) + add_history(lua_tostring(L, 1)); + return 0; +} + +static int f_write_history(lua_State* L) +{ + if (lua_strlen(L,1) > 0) + write_history(lua_tostring(L, 1)); + return 0; +} + +static int f_read_history(lua_State* L) +{ + if (lua_strlen(L,1) > 0) + read_history(lua_tostring(L, 1)); + return 0; +} + +static const struct luaL_reg lib[] = { + {"readline", f_readline}, + {"add_history",f_add_history}, + {"write_history",f_write_history}, + {"read_history",f_read_history}, + {"setup",f_setup}, + {NULL, NULL}, +}; + +int luaopen_readline (lua_State *L) { + luaL_openlib (L, "readline", lib, 0); + return 1; +} |