Details | Last modification | View Log | RSS feed
Rev | Author | Line No. | Line |
---|---|---|---|
5205 | clevermous | 1 | /* |
2 | ** $Id: ltablib.c,v 1.63 2011/11/28 17:26:30 roberto Exp $ |
||
3 | ** Library for Table Manipulation |
||
4 | ** See Copyright Notice in lua.h |
||
5 | */ |
||
6 | |||
7 | |||
8 | #include |
||
9 | |||
10 | #define ltablib_c |
||
11 | #define LUA_LIB |
||
12 | |||
13 | #include "lua.h" |
||
14 | |||
15 | #include "lauxlib.h" |
||
16 | #include "lualib.h" |
||
17 | |||
18 | |||
19 | #define aux_getn(L,n) \ |
||
20 | (luaL_checktype(L, n, LUA_TTABLE), luaL_len(L, n)) |
||
21 | |||
22 | |||
23 | #if defined(LUA_COMPAT_MAXN) |
||
24 | static int maxn (lua_State *L) { |
||
25 | lua_Number max = 0; |
||
26 | luaL_checktype(L, 1, LUA_TTABLE); |
||
27 | lua_pushnil(L); /* first key */ |
||
28 | while (lua_next(L, 1)) { |
||
29 | lua_pop(L, 1); /* remove value */ |
||
30 | if (lua_type(L, -1) == LUA_TNUMBER) { |
||
31 | lua_Number v = lua_tonumber(L, -1); |
||
32 | if (v > max) max = v; |
||
33 | } |
||
34 | } |
||
35 | lua_pushnumber(L, max); |
||
36 | return 1; |
||
37 | } |
||
38 | #endif |
||
39 | |||
40 | |||
41 | static int tinsert (lua_State *L) { |
||
42 | int e = aux_getn(L, 1) + 1; /* first empty element */ |
||
43 | int pos; /* where to insert new element */ |
||
44 | switch (lua_gettop(L)) { |
||
45 | case 2: { /* called with only 2 arguments */ |
||
46 | pos = e; /* insert new element at the end */ |
||
47 | break; |
||
48 | } |
||
49 | case 3: { |
||
50 | int i; |
||
51 | pos = luaL_checkint(L, 2); /* 2nd argument is the position */ |
||
52 | if (pos > e) e = pos; /* `grow' array if necessary */ |
||
53 | for (i = e; i > pos; i--) { /* move up elements */ |
||
54 | lua_rawgeti(L, 1, i-1); |
||
55 | lua_rawseti(L, 1, i); /* t[i] = t[i-1] */ |
||
56 | } |
||
57 | break; |
||
58 | } |
||
59 | default: { |
||
60 | return luaL_error(L, "wrong number of arguments to " LUA_QL("insert")); |
||
61 | } |
||
62 | } |
||
63 | lua_rawseti(L, 1, pos); /* t[pos] = v */ |
||
64 | return 0; |
||
65 | } |
||
66 | |||
67 | |||
68 | static int tremove (lua_State *L) { |
||
69 | int e = aux_getn(L, 1); |
||
70 | int pos = luaL_optint(L, 2, e); |
||
71 | if (!(1 <= pos && pos <= e)) /* position is outside bounds? */ |
||
72 | return 0; /* nothing to remove */ |
||
73 | lua_rawgeti(L, 1, pos); /* result = t[pos] */ |
||
74 | for ( ;pos |
||
75 | lua_rawgeti(L, 1, pos+1); |
||
76 | lua_rawseti(L, 1, pos); /* t[pos] = t[pos+1] */ |
||
77 | } |
||
78 | lua_pushnil(L); |
||
79 | lua_rawseti(L, 1, e); /* t[e] = nil */ |
||
80 | return 1; |
||
81 | } |
||
82 | |||
83 | |||
84 | static void addfield (lua_State *L, luaL_Buffer *b, int i) { |
||
85 | lua_rawgeti(L, 1, i); |
||
86 | if (!lua_isstring(L, -1)) |
||
87 | luaL_error(L, "invalid value (%s) at index %d in table for " |
||
88 | LUA_QL("concat"), luaL_typename(L, -1), i); |
||
89 | luaL_addvalue(b); |
||
90 | } |
||
91 | |||
92 | |||
93 | static int tconcat (lua_State *L) { |
||
94 | luaL_Buffer b; |
||
95 | size_t lsep; |
||
96 | int i, last; |
||
97 | const char *sep = luaL_optlstring(L, 2, "", &lsep); |
||
98 | luaL_checktype(L, 1, LUA_TTABLE); |
||
99 | i = luaL_optint(L, 3, 1); |
||
100 | last = luaL_opt(L, luaL_checkint, 4, luaL_len(L, 1)); |
||
101 | luaL_buffinit(L, &b); |
||
102 | for (; i < last; i++) { |
||
103 | addfield(L, &b, i); |
||
104 | luaL_addlstring(&b, sep, lsep); |
||
105 | } |
||
106 | if (i == last) /* add last value (if interval was not empty) */ |
||
107 | addfield(L, &b, i); |
||
108 | luaL_pushresult(&b); |
||
109 | return 1; |
||
110 | } |
||
111 | |||
112 | |||
113 | /* |
||
114 | ** {====================================================== |
||
115 | ** Pack/unpack |
||
116 | ** ======================================================= |
||
117 | */ |
||
118 | |||
119 | static int pack (lua_State *L) { |
||
120 | int n = lua_gettop(L); /* number of elements to pack */ |
||
121 | lua_createtable(L, n, 1); /* create result table */ |
||
122 | lua_pushinteger(L, n); |
||
123 | lua_setfield(L, -2, "n"); /* t.n = number of elements */ |
||
124 | if (n > 0) { /* at least one element? */ |
||
125 | int i; |
||
126 | lua_pushvalue(L, 1); |
||
127 | lua_rawseti(L, -2, 1); /* insert first element */ |
||
128 | lua_replace(L, 1); /* move table into index 1 */ |
||
129 | for (i = n; i >= 2; i--) /* assign other elements */ |
||
130 | lua_rawseti(L, 1, i); |
||
131 | } |
||
132 | return 1; /* return table */ |
||
133 | } |
||
134 | |||
135 | |||
136 | static int unpack (lua_State *L) { |
||
137 | int i, e, n; |
||
138 | luaL_checktype(L, 1, LUA_TTABLE); |
||
139 | i = luaL_optint(L, 2, 1); |
||
140 | e = luaL_opt(L, luaL_checkint, 3, luaL_len(L, 1)); |
||
141 | if (i > e) return 0; /* empty range */ |
||
142 | n = e - i + 1; /* number of elements */ |
||
143 | if (n <= 0 || !lua_checkstack(L, n)) /* n <= 0 means arith. overflow */ |
||
144 | return luaL_error(L, "too many results to unpack"); |
||
145 | lua_rawgeti(L, 1, i); /* push arg[i] (avoiding overflow problems) */ |
||
146 | while (i++ < e) /* push arg[i + 1...e] */ |
||
147 | lua_rawgeti(L, 1, i); |
||
148 | return n; |
||
149 | } |
||
150 | |||
151 | /* }====================================================== */ |
||
152 | |||
153 | |||
154 | |||
155 | /* |
||
156 | ** {====================================================== |
||
157 | ** Quicksort |
||
158 | ** (based on `Algorithms in MODULA-3', Robert Sedgewick; |
||
159 | ** Addison-Wesley, 1993.) |
||
160 | ** ======================================================= |
||
161 | */ |
||
162 | |||
163 | |||
164 | static void set2 (lua_State *L, int i, int j) { |
||
165 | lua_rawseti(L, 1, i); |
||
166 | lua_rawseti(L, 1, j); |
||
167 | } |
||
168 | |||
169 | static int sort_comp (lua_State *L, int a, int b) { |
||
170 | if (!lua_isnil(L, 2)) { /* function? */ |
||
171 | int res; |
||
172 | lua_pushvalue(L, 2); |
||
173 | lua_pushvalue(L, a-1); /* -1 to compensate function */ |
||
174 | lua_pushvalue(L, b-2); /* -2 to compensate function and `a' */ |
||
175 | lua_call(L, 2, 1); |
||
176 | res = lua_toboolean(L, -1); |
||
177 | lua_pop(L, 1); |
||
178 | return res; |
||
179 | } |
||
180 | else /* a < b? */ |
||
181 | return lua_compare(L, a, b, LUA_OPLT); |
||
182 | } |
||
183 | |||
184 | static void auxsort (lua_State *L, int l, int u) { |
||
185 | while (l < u) { /* for tail recursion */ |
||
186 | int i, j; |
||
187 | /* sort elements a[l], a[(l+u)/2] and a[u] */ |
||
188 | lua_rawgeti(L, 1, l); |
||
189 | lua_rawgeti(L, 1, u); |
||
190 | if (sort_comp(L, -1, -2)) /* a[u] < a[l]? */ |
||
191 | set2(L, l, u); /* swap a[l] - a[u] */ |
||
192 | else |
||
193 | lua_pop(L, 2); |
||
194 | if (u-l == 1) break; /* only 2 elements */ |
||
195 | i = (l+u)/2; |
||
196 | lua_rawgeti(L, 1, i); |
||
197 | lua_rawgeti(L, 1, l); |
||
198 | if (sort_comp(L, -2, -1)) /* a[i] |
||
199 | set2(L, i, l); |
||
200 | else { |
||
201 | lua_pop(L, 1); /* remove a[l] */ |
||
202 | lua_rawgeti(L, 1, u); |
||
203 | if (sort_comp(L, -1, -2)) /* a[u] |
||
204 | set2(L, i, u); |
||
205 | else |
||
206 | lua_pop(L, 2); |
||
207 | } |
||
208 | if (u-l == 2) break; /* only 3 elements */ |
||
209 | lua_rawgeti(L, 1, i); /* Pivot */ |
||
210 | lua_pushvalue(L, -1); |
||
211 | lua_rawgeti(L, 1, u-1); |
||
212 | set2(L, i, u-1); |
||
213 | /* a[l] <= P == a[u-1] <= a[u], only need to sort from l+1 to u-2 */ |
||
214 | i = l; j = u-1; |
||
215 | for (;;) { /* invariant: a[l..i] <= P <= a[j..u] */ |
||
216 | /* repeat ++i until a[i] >= P */ |
||
217 | while (lua_rawgeti(L, 1, ++i), sort_comp(L, -1, -2)) { |
||
218 | if (i>=u) luaL_error(L, "invalid order function for sorting"); |
||
219 | lua_pop(L, 1); /* remove a[i] */ |
||
220 | } |
||
221 | /* repeat --j until a[j] <= P */ |
||
222 | while (lua_rawgeti(L, 1, --j), sort_comp(L, -3, -1)) { |
||
223 | if (j<=l) luaL_error(L, "invalid order function for sorting"); |
||
224 | lua_pop(L, 1); /* remove a[j] */ |
||
225 | } |
||
226 | if (j |
||
227 | lua_pop(L, 3); /* pop pivot, a[i], a[j] */ |
||
228 | break; |
||
229 | } |
||
230 | set2(L, i, j); |
||
231 | } |
||
232 | lua_rawgeti(L, 1, u-1); |
||
233 | lua_rawgeti(L, 1, i); |
||
234 | set2(L, u-1, i); /* swap pivot (a[u-1]) with a[i] */ |
||
235 | /* a[l..i-1] <= a[i] == P <= a[i+1..u] */ |
||
236 | /* adjust so that smaller half is in [j..i] and larger one in [l..u] */ |
||
237 | if (i-l < u-i) { |
||
238 | j=l; i=i-1; l=i+2; |
||
239 | } |
||
240 | else { |
||
241 | j=i+1; i=u; u=j-2; |
||
242 | } |
||
243 | auxsort(L, j, i); /* call recursively the smaller one */ |
||
244 | } /* repeat the routine for the larger one */ |
||
245 | } |
||
246 | |||
247 | static int sort (lua_State *L) { |
||
248 | int n = aux_getn(L, 1); |
||
249 | luaL_checkstack(L, 40, ""); /* assume array is smaller than 2^40 */ |
||
250 | if (!lua_isnoneornil(L, 2)) /* is there a 2nd argument? */ |
||
251 | luaL_checktype(L, 2, LUA_TFUNCTION); |
||
252 | lua_settop(L, 2); /* make sure there is two arguments */ |
||
253 | auxsort(L, 1, n); |
||
254 | return 0; |
||
255 | } |
||
256 | |||
257 | /* }====================================================== */ |
||
258 | |||
259 | |||
260 | static const luaL_Reg tab_funcs[] = { |
||
261 | {"concat", tconcat}, |
||
262 | #if defined(LUA_COMPAT_MAXN) |
||
263 | {"maxn", maxn}, |
||
264 | #endif |
||
265 | {"insert", tinsert}, |
||
266 | {"pack", pack}, |
||
267 | {"unpack", unpack}, |
||
268 | {"remove", tremove}, |
||
269 | {"sort", sort}, |
||
270 | {NULL, NULL} |
||
271 | }; |
||
272 | |||
273 | |||
274 | LUAMOD_API int luaopen_table (lua_State *L) { |
||
275 | luaL_newlib(L, tab_funcs); |
||
276 | #if defined(LUA_COMPAT_UNPACK) |
||
277 | /* _G.unpack = table.unpack */ |
||
278 | lua_getfield(L, -1, "unpack"); |
||
279 | lua_setglobal(L, "unpack"); |
||
280 | #endif |
||
281 | return 1; |
||
282 | }>=>=>=l)>=>=>=>=>=>>>>>=>=>>=>=> |
||
283 |