util.ringbuffer: Add various comments

This commit is contained in:
Kim Alvefur 2018-02-24 14:44:46 +01:00
parent e2a3b634fb
commit a92cdf75b1

View file

@ -39,10 +39,12 @@ int find(ringbuffer *b, const char *s, size_t l) {
return 0;
}
/* look for a matching first byte */
for(i = 0; i <= b->blen - l; i++) {
if(b->buffer[(b->rpos + i) % b->alen] == *s) {
m = 1;
/* check if the following byte also match */
for(j = 1; j < l; j++)
if(b->buffer[(b->rpos + i + j) % b->alen] != s[j]) {
m = 0;
@ -58,6 +60,10 @@ int find(ringbuffer *b, const char *s, size_t l) {
return 0;
}
/*
* Find first position of a substring in buffer
* (buffer, string) -> number
*/
int rb_find(lua_State *L) {
size_t l, m;
ringbuffer *b = luaL_checkudata(L, 1, "ringbuffer_mt");
@ -72,6 +78,10 @@ int rb_find(lua_State *L) {
return 0;
}
/*
* Read bytes from buffer
* (buffer, number, boolean?) -> string
*/
int rb_read(lua_State *L) {
ringbuffer *b = luaL_checkudata(L, 1, "ringbuffer_mt");
size_t r = luaL_checkinteger(L, 2);
@ -83,6 +93,7 @@ int rb_read(lua_State *L) {
}
if((b->rpos + r) > b->alen) {
/* Substring wraps around to the beginning of the buffer */
lua_pushlstring(L, &b->buffer[b->rpos], b->alen - b->rpos);
lua_pushlstring(L, b->buffer, r - (b->alen - b->rpos));
lua_concat(L, 2);
@ -99,6 +110,10 @@ int rb_read(lua_State *L) {
return 1;
}
/*
* Read buffer until first occurence of a substring
* (buffer, string) -> string
*/
int rb_readuntil(lua_State *L) {
size_t l, m;
ringbuffer *b = luaL_checkudata(L, 1, "ringbuffer_mt");
@ -114,6 +129,10 @@ int rb_readuntil(lua_State *L) {
return 0;
}
/*
* Write bytes into the buffer
* (buffer, string) -> integer
*/
int rb_write(lua_State *L) {
size_t l, w = 0;
ringbuffer *b = luaL_checkudata(L, 1, "ringbuffer_mt");