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16a5fed6 | 1 | /*\r |
2 | ** $Id: ltablib.c,v 1.65.1.1 2013/04/12 18:48:47 roberto Exp $\r | |
3 | ** Library for Table Manipulation\r | |
4 | ** See Copyright Notice in lua.h\r | |
5 | */\r | |
6 | \r | |
7 | \r | |
8 | #include <stddef.h>\r | |
9 | \r | |
10 | #define ltablib_c\r | |
11 | #define LUA_LIB\r | |
12 | \r | |
13 | #include "lua.h"\r | |
14 | \r | |
15 | #include "lauxlib.h"\r | |
16 | #include "lualib.h"\r | |
17 | \r | |
18 | \r | |
19 | #define aux_getn(L,n) (luaL_checktype(L, n, LUA_TTABLE), luaL_len(L, n))\r | |
20 | \r | |
21 | \r | |
22 | \r | |
23 | #if defined(LUA_COMPAT_MAXN)\r | |
24 | static int maxn (lua_State *L) {\r | |
25 | lua_Number max = 0;\r | |
26 | luaL_checktype(L, 1, LUA_TTABLE);\r | |
27 | lua_pushnil(L); /* first key */\r | |
28 | while (lua_next(L, 1)) {\r | |
29 | lua_pop(L, 1); /* remove value */\r | |
30 | if (lua_type(L, -1) == LUA_TNUMBER) {\r | |
31 | lua_Number v = lua_tonumber(L, -1);\r | |
32 | if (v > max) max = v;\r | |
33 | }\r | |
34 | }\r | |
35 | lua_pushnumber(L, max);\r | |
36 | return 1;\r | |
37 | }\r | |
38 | #endif\r | |
39 | \r | |
40 | \r | |
41 | static int tinsert (lua_State *L) {\r | |
42 | int e = aux_getn(L, 1) + 1; /* first empty element */\r | |
43 | int pos; /* where to insert new element */\r | |
44 | switch (lua_gettop(L)) {\r | |
45 | case 2: { /* called with only 2 arguments */\r | |
46 | pos = e; /* insert new element at the end */\r | |
47 | break;\r | |
48 | }\r | |
49 | case 3: {\r | |
50 | int i;\r | |
51 | pos = luaL_checkint(L, 2); /* 2nd argument is the position */\r | |
52 | luaL_argcheck(L, 1 <= pos && pos <= e, 2, "position out of bounds");\r | |
53 | for (i = e; i > pos; i--) { /* move up elements */\r | |
54 | lua_rawgeti(L, 1, i-1);\r | |
55 | lua_rawseti(L, 1, i); /* t[i] = t[i-1] */\r | |
56 | }\r | |
57 | break;\r | |
58 | }\r | |
59 | default: {\r | |
60 | return luaL_error(L, "wrong number of arguments to " LUA_QL("insert"));\r | |
61 | }\r | |
62 | }\r | |
63 | lua_rawseti(L, 1, pos); /* t[pos] = v */\r | |
64 | return 0;\r | |
65 | }\r | |
66 | \r | |
67 | \r | |
68 | static int tremove (lua_State *L) {\r | |
69 | int size = aux_getn(L, 1);\r | |
70 | int pos = luaL_optint(L, 2, size);\r | |
71 | if (pos != size) /* validate 'pos' if given */\r | |
72 | luaL_argcheck(L, 1 <= pos && pos <= size + 1, 1, "position out of bounds");\r | |
73 | lua_rawgeti(L, 1, pos); /* result = t[pos] */\r | |
74 | for ( ; pos < size; pos++) {\r | |
75 | lua_rawgeti(L, 1, pos+1);\r | |
76 | lua_rawseti(L, 1, pos); /* t[pos] = t[pos+1] */\r | |
77 | }\r | |
78 | lua_pushnil(L);\r | |
79 | lua_rawseti(L, 1, pos); /* t[pos] = nil */\r | |
80 | return 1;\r | |
81 | }\r | |
82 | \r | |
83 | \r | |
84 | static void addfield (lua_State *L, luaL_Buffer *b, int i) {\r | |
85 | lua_rawgeti(L, 1, i);\r | |
86 | if (!lua_isstring(L, -1))\r | |
87 | luaL_error(L, "invalid value (%s) at index %d in table for "\r | |
88 | LUA_QL("concat"), luaL_typename(L, -1), i);\r | |
89 | luaL_addvalue(b);\r | |
90 | }\r | |
91 | \r | |
92 | \r | |
93 | static int tconcat (lua_State *L) {\r | |
94 | luaL_Buffer b;\r | |
95 | size_t lsep;\r | |
96 | int i, last;\r | |
97 | const char *sep = luaL_optlstring(L, 2, "", &lsep);\r | |
98 | luaL_checktype(L, 1, LUA_TTABLE);\r | |
99 | i = luaL_optint(L, 3, 1);\r | |
100 | last = luaL_opt(L, luaL_checkint, 4, luaL_len(L, 1));\r | |
101 | luaL_buffinit(L, &b);\r | |
102 | for (; i < last; i++) {\r | |
103 | addfield(L, &b, i);\r | |
104 | luaL_addlstring(&b, sep, lsep);\r | |
105 | }\r | |
106 | if (i == last) /* add last value (if interval was not empty) */\r | |
107 | addfield(L, &b, i);\r | |
108 | luaL_pushresult(&b);\r | |
109 | return 1;\r | |
110 | }\r | |
111 | \r | |
112 | \r | |
113 | /*\r | |
114 | ** {======================================================\r | |
115 | ** Pack/unpack\r | |
116 | ** =======================================================\r | |
117 | */\r | |
118 | \r | |
119 | static int pack (lua_State *L) {\r | |
120 | int n = lua_gettop(L); /* number of elements to pack */\r | |
121 | lua_createtable(L, n, 1); /* create result table */\r | |
122 | lua_pushinteger(L, n);\r | |
123 | lua_setfield(L, -2, "n"); /* t.n = number of elements */\r | |
124 | if (n > 0) { /* at least one element? */\r | |
125 | int i;\r | |
126 | lua_pushvalue(L, 1);\r | |
127 | lua_rawseti(L, -2, 1); /* insert first element */\r | |
128 | lua_replace(L, 1); /* move table into index 1 */\r | |
129 | for (i = n; i >= 2; i--) /* assign other elements */\r | |
130 | lua_rawseti(L, 1, i);\r | |
131 | }\r | |
132 | return 1; /* return table */\r | |
133 | }\r | |
134 | \r | |
135 | \r | |
136 | static int unpack (lua_State *L) {\r | |
137 | int i, e, n;\r | |
138 | luaL_checktype(L, 1, LUA_TTABLE);\r | |
139 | i = luaL_optint(L, 2, 1);\r | |
140 | e = luaL_opt(L, luaL_checkint, 3, luaL_len(L, 1));\r | |
141 | if (i > e) return 0; /* empty range */\r | |
142 | n = e - i + 1; /* number of elements */\r | |
143 | if (n <= 0 || !lua_checkstack(L, n)) /* n <= 0 means arith. overflow */\r | |
144 | return luaL_error(L, "too many results to unpack");\r | |
145 | lua_rawgeti(L, 1, i); /* push arg[i] (avoiding overflow problems) */\r | |
146 | while (i++ < e) /* push arg[i + 1...e] */\r | |
147 | lua_rawgeti(L, 1, i);\r | |
148 | return n;\r | |
149 | }\r | |
150 | \r | |
151 | /* }====================================================== */\r | |
152 | \r | |
153 | \r | |
154 | \r | |
155 | /*\r | |
156 | ** {======================================================\r | |
157 | ** Quicksort\r | |
158 | ** (based on `Algorithms in MODULA-3', Robert Sedgewick;\r | |
159 | ** Addison-Wesley, 1993.)\r | |
160 | ** =======================================================\r | |
161 | */\r | |
162 | \r | |
163 | \r | |
164 | static void set2 (lua_State *L, int i, int j) {\r | |
165 | lua_rawseti(L, 1, i);\r | |
166 | lua_rawseti(L, 1, j);\r | |
167 | }\r | |
168 | \r | |
169 | static int sort_comp (lua_State *L, int a, int b) {\r | |
170 | if (!lua_isnil(L, 2)) { /* function? */\r | |
171 | int res;\r | |
172 | lua_pushvalue(L, 2);\r | |
173 | lua_pushvalue(L, a-1); /* -1 to compensate function */\r | |
174 | lua_pushvalue(L, b-2); /* -2 to compensate function and `a' */\r | |
175 | lua_call(L, 2, 1);\r | |
176 | res = lua_toboolean(L, -1);\r | |
177 | lua_pop(L, 1);\r | |
178 | return res;\r | |
179 | }\r | |
180 | else /* a < b? */\r | |
181 | return lua_compare(L, a, b, LUA_OPLT);\r | |
182 | }\r | |
183 | \r | |
184 | static void auxsort (lua_State *L, int l, int u) {\r | |
185 | while (l < u) { /* for tail recursion */\r | |
186 | int i, j;\r | |
187 | /* sort elements a[l], a[(l+u)/2] and a[u] */\r | |
188 | lua_rawgeti(L, 1, l);\r | |
189 | lua_rawgeti(L, 1, u);\r | |
190 | if (sort_comp(L, -1, -2)) /* a[u] < a[l]? */\r | |
191 | set2(L, l, u); /* swap a[l] - a[u] */\r | |
192 | else\r | |
193 | lua_pop(L, 2);\r | |
194 | if (u-l == 1) break; /* only 2 elements */\r | |
195 | i = (l+u)/2;\r | |
196 | lua_rawgeti(L, 1, i);\r | |
197 | lua_rawgeti(L, 1, l);\r | |
198 | if (sort_comp(L, -2, -1)) /* a[i]<a[l]? */\r | |
199 | set2(L, i, l);\r | |
200 | else {\r | |
201 | lua_pop(L, 1); /* remove a[l] */\r | |
202 | lua_rawgeti(L, 1, u);\r | |
203 | if (sort_comp(L, -1, -2)) /* a[u]<a[i]? */\r | |
204 | set2(L, i, u);\r | |
205 | else\r | |
206 | lua_pop(L, 2);\r | |
207 | }\r | |
208 | if (u-l == 2) break; /* only 3 elements */\r | |
209 | lua_rawgeti(L, 1, i); /* Pivot */\r | |
210 | lua_pushvalue(L, -1);\r | |
211 | lua_rawgeti(L, 1, u-1);\r | |
212 | set2(L, i, u-1);\r | |
213 | /* a[l] <= P == a[u-1] <= a[u], only need to sort from l+1 to u-2 */\r | |
214 | i = l; j = u-1;\r | |
215 | for (;;) { /* invariant: a[l..i] <= P <= a[j..u] */\r | |
216 | /* repeat ++i until a[i] >= P */\r | |
217 | while (lua_rawgeti(L, 1, ++i), sort_comp(L, -1, -2)) {\r | |
218 | if (i>=u) luaL_error(L, "invalid order function for sorting");\r | |
219 | lua_pop(L, 1); /* remove a[i] */\r | |
220 | }\r | |
221 | /* repeat --j until a[j] <= P */\r | |
222 | while (lua_rawgeti(L, 1, --j), sort_comp(L, -3, -1)) {\r | |
223 | if (j<=l) luaL_error(L, "invalid order function for sorting");\r | |
224 | lua_pop(L, 1); /* remove a[j] */\r | |
225 | }\r | |
226 | if (j<i) {\r | |
227 | lua_pop(L, 3); /* pop pivot, a[i], a[j] */\r | |
228 | break;\r | |
229 | }\r | |
230 | set2(L, i, j);\r | |
231 | }\r | |
232 | lua_rawgeti(L, 1, u-1);\r | |
233 | lua_rawgeti(L, 1, i);\r | |
234 | set2(L, u-1, i); /* swap pivot (a[u-1]) with a[i] */\r | |
235 | /* a[l..i-1] <= a[i] == P <= a[i+1..u] */\r | |
236 | /* adjust so that smaller half is in [j..i] and larger one in [l..u] */\r | |
237 | if (i-l < u-i) {\r | |
238 | j=l; i=i-1; l=i+2;\r | |
239 | }\r | |
240 | else {\r | |
241 | j=i+1; i=u; u=j-2;\r | |
242 | }\r | |
243 | auxsort(L, j, i); /* call recursively the smaller one */\r | |
244 | } /* repeat the routine for the larger one */\r | |
245 | }\r | |
246 | \r | |
247 | static int sort (lua_State *L) {\r | |
248 | int n = aux_getn(L, 1);\r | |
249 | luaL_checkstack(L, 40, ""); /* assume array is smaller than 2^40 */\r | |
250 | if (!lua_isnoneornil(L, 2)) /* is there a 2nd argument? */\r | |
251 | luaL_checktype(L, 2, LUA_TFUNCTION);\r | |
252 | lua_settop(L, 2); /* make sure there is two arguments */\r | |
253 | auxsort(L, 1, n);\r | |
254 | return 0;\r | |
255 | }\r | |
256 | \r | |
257 | /* }====================================================== */\r | |
258 | \r | |
259 | \r | |
260 | static const luaL_Reg tab_funcs[] = {\r | |
261 | {"concat", tconcat},\r | |
262 | #if defined(LUA_COMPAT_MAXN)\r | |
263 | {"maxn", maxn},\r | |
264 | #endif\r | |
265 | {"insert", tinsert},\r | |
266 | {"pack", pack},\r | |
267 | {"unpack", unpack},\r | |
268 | {"remove", tremove},\r | |
269 | {"sort", sort},\r | |
270 | {NULL, NULL}\r | |
271 | };\r | |
272 | \r | |
273 | \r | |
274 | LUAMOD_API int luaopen_table (lua_State *L) {\r | |
275 | luaL_newlib(L, tab_funcs);\r | |
276 | #if defined(LUA_COMPAT_UNPACK)\r | |
277 | /* _G.unpack = table.unpack */\r | |
278 | lua_getfield(L, -1, "unpack");\r | |
279 | lua_setglobal(L, "unpack");\r | |
280 | #endif\r | |
281 | return 1;\r | |
282 | }\r | |
283 | \r |