Mercurial > prosody-hg

comparison util-src/ringbuffer.c @ 7828:b4a08a514ebc

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util.ringbuffer: Allocate buffer itself as part of userdata (simpler, single allocation, no need for __gc)
author Kim Alvefur <zash@zash.se>
date Sun, 22 Jan 2017 09:23:10 +0100
parents db15e9f6d77f
children a809dcfd0c5b
comparison
equal deleted inserted replaced
7827:db15e9f6d77f 7828:b4a08a514ebc
11 typedef struct { 11 typedef struct {
12 size_t rpos; /* read position */ 12 size_t rpos; /* read position */
13 size_t wpos; /* write position */ 13 size_t wpos; /* write position */
14 size_t alen; /* allocated size */ 14 size_t alen; /* allocated size */
15 size_t blen; /* current content size */ 15 size_t blen; /* current content size */
16 char* buffer; 16 char buffer[];
17 } ringbuffer; 17 } ringbuffer;
18 18
19 char readchar(ringbuffer* b) { 19 char readchar(ringbuffer* b) {
20 b->blen--; 20 b->blen--;
21 return b->buffer[(b->rpos++) % b->alen]; 21 return b->buffer[(b->rpos++) % b->alen];
164 return 1; 164 return 1;
165 } 165 }
166 166
167 int rb_new(lua_State* L) { 167 int rb_new(lua_State* L) {
168 size_t size = luaL_optinteger(L, 1, sysconf(_SC_PAGESIZE)); 168 size_t size = luaL_optinteger(L, 1, sysconf(_SC_PAGESIZE));
169 ringbuffer* b = lua_newuserdata(L, sizeof(ringbuffer)); 169 ringbuffer *b = lua_newuserdata(L, sizeof(ringbuffer) + size);
170
170 b->rpos = 0; 171 b->rpos = 0;
171 b->wpos = 0; 172 b->wpos = 0;
172 b->alen = size; 173 b->alen = size;
173 b->blen = 0; 174 b->blen = 0;
174 b->buffer = malloc(size);
175
176 if(b->buffer == NULL) {
177 return 0;
178 }
179 175
180 luaL_getmetatable(L, "ringbuffer_mt"); 176 luaL_getmetatable(L, "ringbuffer_mt");
181 lua_setmetatable(L, -2); 177 lua_setmetatable(L, -2);
182 178
183 return 1; 179 return 1;
184 }
185
186 int rb_gc(lua_State* L) {
187 ringbuffer* b = luaL_checkudata(L, 1, "ringbuffer_mt");
188
189 if(b->buffer != NULL) {
190 free(b->buffer);
191 }
192
193 return 0;
194 } 180 }
195 181
196 int luaopen_util_ringbuffer(lua_State* L) { 182 int luaopen_util_ringbuffer(lua_State* L) {
197 #if (LUA_VERSION_NUM > 501) 183 #if (LUA_VERSION_NUM > 501)
198 luaL_checkversion(L); 184 luaL_checkversion(L);
200 if(luaL_newmetatable(L, "ringbuffer_mt")) { 186 if(luaL_newmetatable(L, "ringbuffer_mt")) {
201 lua_pushcfunction(L, rb_tostring); 187 lua_pushcfunction(L, rb_tostring);
202 lua_setfield(L, -2, "__tostring"); 188 lua_setfield(L, -2, "__tostring");
203 lua_pushcfunction(L, rb_length); 189 lua_pushcfunction(L, rb_length);
204 lua_setfield(L, -2, "__len"); 190 lua_setfield(L, -2, "__len");
205 lua_pushcfunction(L, rb_gc);
206 lua_setfield(L, -2, "__gc");
207 191
208 lua_newtable(L); /* __index */ 192 lua_newtable(L); /* __index */
209 { 193 {
210 lua_pushcfunction(L, rb_find); 194 lua_pushcfunction(L, rb_find);
211 lua_setfield(L, -2, "find"); 195 lua_setfield(L, -2, "find");