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author | Roberto Ierusalimschy <roberto@inf.puc-rio.br> | 2013-04-12 15:48:47 -0300 |
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committer | Roberto Ierusalimschy <roberto@inf.puc-rio.br> | 2013-04-12 15:48:47 -0300 |
commit | 2ca518141350667e38941eac35b76980095d2fdc (patch) | |
tree | 82595f0dfd57df5782905621298c8aae68b46389 /ltablib.c | |
parent | f5ae26ec6c2eb69f03f316e59c1e1977c52c7c23 (diff) | |
download | lua-2ca518141350667e38941eac35b76980095d2fdc.tar.gz lua-2ca518141350667e38941eac35b76980095d2fdc.tar.bz2 lua-2ca518141350667e38941eac35b76980095d2fdc.zip |
Branch 5.2 - new releases for 5.2 go from here, main trunk goes
for next version
Diffstat (limited to 'ltablib.c')
-rw-r--r-- | ltablib.c | 283 |
1 files changed, 283 insertions, 0 deletions
diff --git a/ltablib.c b/ltablib.c new file mode 100644 index 00000000..ad798b4e --- /dev/null +++ b/ltablib.c | |||
@@ -0,0 +1,283 @@ | |||
1 | /* | ||
2 | ** $Id: ltablib.c,v 1.65 2013/03/07 18:17:24 roberto Exp $ | ||
3 | ** Library for Table Manipulation | ||
4 | ** See Copyright Notice in lua.h | ||
5 | */ | ||
6 | |||
7 | |||
8 | #include <stddef.h> | ||
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) (luaL_checktype(L, n, LUA_TTABLE), luaL_len(L, n)) | ||
20 | |||
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 | luaL_argcheck(L, 1 <= pos && pos <= e, 2, "position out of bounds"); | ||
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 size = aux_getn(L, 1); | ||
70 | int pos = luaL_optint(L, 2, size); | ||
71 | if (pos != size) /* validate 'pos' if given */ | ||
72 | luaL_argcheck(L, 1 <= pos && pos <= size + 1, 1, "position out of bounds"); | ||
73 | lua_rawgeti(L, 1, pos); /* result = t[pos] */ | ||
74 | for ( ; pos < size; 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, pos); /* t[pos] = 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]<a[l]? */ | ||
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]<a[i]? */ | ||
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<i) { | ||
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 | } | ||
283 | |||