mirror of
https://github.com/lua/lua
synced 2025-01-01 15:14:35 +03:00
new implementation for Generic Buffer manipulation (using userdata as
temporary buffer space)
This commit is contained in:
Roberto Ierusalimschy
parent
055104f5b6
commit
9100f7479a
124
lauxlib.c
124
lauxlib.c
@ -1,5 +1,5 @@
|
||||
/*
|
||||
** $Id: lauxlib.c,v 1.205 2010/03/22 17:28:31 roberto Exp roberto $
|
||||
** $Id: lauxlib.c,v 1.206 2010/03/29 17:44:31 roberto Exp roberto $
|
||||
** Auxiliary functions for building Lua libraries
|
||||
** See Copyright Notice in lua.h
|
||||
*/
|
||||
@ -347,64 +347,40 @@ LUALIB_API lua_Integer luaL_optinteger (lua_State *L, int narg,
|
||||
** =======================================================
|
||||
*/
|
||||
|
||||
|
||||
#define bufflen(B) ((B)->p - (B)->buffer)
|
||||
#define bufffree(B) ((size_t)(LUAL_BUFFERSIZE - bufflen(B)))
|
||||
|
||||
#define LIMIT (LUA_MINSTACK/2)
|
||||
/*
|
||||
** check whether buffer is using a userdata on the stack as a temporary
|
||||
** buffer
|
||||
*/
|
||||
#define buffonstack(B) ((B)->b != (B)->initb)
|
||||
|
||||
|
||||
static int emptybuffer (luaL_Buffer *B) {
|
||||
size_t l = bufflen(B);
|
||||
if (l == 0) return 0; /* put nothing on stack */
|
||||
else {
|
||||
lua_pushlstring(B->L, B->buffer, l);
|
||||
B->p = B->buffer;
|
||||
B->lvl++;
|
||||
return 1;
|
||||
/*
|
||||
** returns a pointer to a free area with at least 'sz' bytes
|
||||
*/
|
||||
LUALIB_API char *luaL_prepbuffsize (luaL_Buffer *B, size_t sz) {
|
||||
lua_State *L = B->L;
|
||||
if (B->size - B->n < sz) { /* not enough space? */
|
||||
char *newbuff;
|
||||
size_t newsize = B->size * 2; /* double buffer size */
|
||||
if (newsize - B->n < sz) /* not bit enough? */
|
||||
newsize = B->n + sz;
|
||||
if (newsize < B->n || newsize - B->n < sz)
|
||||
luaL_error(L, "string too large");
|
||||
newbuff = (char *)lua_newuserdata(L, newsize); /* create larger buffer */
|
||||
memcpy(newbuff, B->b, B->n); /* move content to new buffer */
|
||||
if (buffonstack(B))
|
||||
lua_remove(L, -2); /* remove old buffer */
|
||||
B->b = newbuff;
|
||||
B->size = newsize;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
static void adjuststack (luaL_Buffer *B) {
|
||||
if (B->lvl > 1) {
|
||||
lua_State *L = B->L;
|
||||
int toget = 1; /* number of levels to concat */
|
||||
size_t toplen = lua_rawlen(L, -1);
|
||||
do {
|
||||
size_t l = lua_rawlen(L, -(toget+1));
|
||||
if (B->lvl - toget + 1 >= LIMIT || toplen > l) {
|
||||
toplen += l;
|
||||
toget++;
|
||||
}
|
||||
else break;
|
||||
} while (toget < B->lvl);
|
||||
lua_concat(L, toget);
|
||||
B->lvl = B->lvl - toget + 1;
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
LUALIB_API char *luaL_prepbuffer (luaL_Buffer *B) {
|
||||
if (emptybuffer(B))
|
||||
adjuststack(B);
|
||||
return B->buffer;
|
||||
return &B->b[B->n];
|
||||
}
|
||||
|
||||
|
||||
LUALIB_API void luaL_addlstring (luaL_Buffer *B, const char *s, size_t l) {
|
||||
while (l) {
|
||||
size_t space = bufffree(B);
|
||||
if (space == 0) {
|
||||
luaL_prepbuffer(B);
|
||||
space = LUAL_BUFFERSIZE; /* bufffree(B) == LUAL_BUFFERSIZE */
|
||||
}
|
||||
if (space > l) space = l;
|
||||
memcpy(B->p, s, space);
|
||||
B->p += space;
|
||||
s += space;
|
||||
l -= space;
|
||||
}
|
||||
char *b = luaL_prepbuffsize(B, l);
|
||||
memcpy(b, s, l);
|
||||
luaL_addsize(B, l);
|
||||
}
|
||||
|
||||
|
||||
@ -414,35 +390,41 @@ LUALIB_API void luaL_addstring (luaL_Buffer *B, const char *s) {
|
||||
|
||||
|
||||
LUALIB_API void luaL_pushresult (luaL_Buffer *B) {
|
||||
emptybuffer(B);
|
||||
lua_concat(B->L, B->lvl);
|
||||
B->lvl = 1;
|
||||
lua_State *L = B->L;
|
||||
lua_pushlstring(L, B->b, B->n);
|
||||
if (buffonstack(B))
|
||||
lua_remove(L, -2); /* remove old buffer */
|
||||
}
|
||||
|
||||
|
||||
LUALIB_API void luaL_pushresultsize (luaL_Buffer *B, size_t sz) {
|
||||
luaL_addsize(B, sz);
|
||||
luaL_pushresult(B);
|
||||
}
|
||||
|
||||
|
||||
LUALIB_API void luaL_addvalue (luaL_Buffer *B) {
|
||||
lua_State *L = B->L;
|
||||
size_t vl;
|
||||
const char *s = lua_tolstring(L, -1, &vl);
|
||||
if (vl <= bufffree(B)) { /* fit into buffer? */
|
||||
memcpy(B->p, s, vl); /* put it there */
|
||||
B->p += vl;
|
||||
lua_pop(L, 1); /* remove from stack */
|
||||
}
|
||||
else {
|
||||
if (emptybuffer(B))
|
||||
lua_insert(L, -2); /* put buffer before new value */
|
||||
B->lvl++; /* add new value into B stack */
|
||||
adjuststack(B);
|
||||
}
|
||||
size_t l;
|
||||
const char *s = lua_tolstring(L, -1, &l);
|
||||
if (buffonstack(B))
|
||||
lua_insert(L, -2); /* put value below buffer */
|
||||
luaL_addlstring(B, s, l);
|
||||
lua_remove(L, (buffonstack(B)) ? -2 : -1); /* remove value */
|
||||
}
|
||||
|
||||
|
||||
LUALIB_API void luaL_buffinit (lua_State *L, luaL_Buffer *B) {
|
||||
luaL_checkstack(L, LIMIT + LUA_MINSTACK, "no space for new buffer");
|
||||
B->L = L;
|
||||
B->p = B->buffer;
|
||||
B->lvl = 0;
|
||||
B->b = B->initb;
|
||||
B->n = 0;
|
||||
B->size = LUAL_BUFFERSIZE;
|
||||
}
|
||||
|
||||
|
||||
LUALIB_API char *luaL_buffinitsize (lua_State *L, luaL_Buffer *B, size_t sz) {
|
||||
luaL_buffinit(L, B);
|
||||
return luaL_prepbuffsize(B, sz);
|
||||
}
|
||||
|
||||
/* }====================================================== */
|
||||
|
||||
25
lauxlib.h
25
lauxlib.h
@ -1,5 +1,5 @@
|
||||
/*
|
||||
** $Id: lauxlib.h,v 1.100 2010/01/21 16:49:21 roberto Exp roberto $
|
||||
** $Id: lauxlib.h,v 1.101 2010/03/17 21:37:37 roberto Exp roberto $
|
||||
** Auxiliary functions for building Lua libraries
|
||||
** See Copyright Notice in lua.h
|
||||
*/
|
||||
@ -122,28 +122,31 @@ LUALIB_API int (luaL_cpcall) (lua_State *L, lua_CFunction f, int nargs,
|
||||
** =======================================================
|
||||
*/
|
||||
|
||||
|
||||
|
||||
typedef struct luaL_Buffer {
|
||||
char *p; /* current position in buffer */
|
||||
int lvl; /* number of strings in the stack (level) */
|
||||
char *b; /* buffer address */
|
||||
size_t size; /* buffer size */
|
||||
size_t n; /* number of characters in buffer */
|
||||
lua_State *L;
|
||||
char buffer[LUAL_BUFFERSIZE];
|
||||
char initb[LUAL_BUFFERSIZE]; /* initial buffer */
|
||||
} luaL_Buffer;
|
||||
|
||||
#define luaL_addchar(B,c) \
|
||||
((void)((B)->p < ((B)->buffer+LUAL_BUFFERSIZE) || luaL_prepbuffer(B)), \
|
||||
(*(B)->p++ = (char)(c)))
|
||||
|
||||
#define luaL_addsize(B,n) ((B)->p += (n))
|
||||
#define luaL_addchar(B,c) \
|
||||
((void)((B)->n < (B)->size || luaL_prepbuffsize((B), 1)), \
|
||||
((B)->b[(B)->n++] = (c)))
|
||||
|
||||
#define luaL_addsize(B,s) ((B)->n += (s))
|
||||
|
||||
LUALIB_API void (luaL_buffinit) (lua_State *L, luaL_Buffer *B);
|
||||
LUALIB_API char *(luaL_prepbuffer) (luaL_Buffer *B);
|
||||
LUALIB_API char *(luaL_prepbuffsize) (luaL_Buffer *B, size_t sz);
|
||||
LUALIB_API void (luaL_addlstring) (luaL_Buffer *B, const char *s, size_t l);
|
||||
LUALIB_API void (luaL_addstring) (luaL_Buffer *B, const char *s);
|
||||
LUALIB_API void (luaL_addvalue) (luaL_Buffer *B);
|
||||
LUALIB_API void (luaL_pushresult) (luaL_Buffer *B);
|
||||
LUALIB_API void luaL_pushresultsize (luaL_Buffer *B, size_t sz);
|
||||
LUALIB_API char *(luaL_buffinitsize) (lua_State *L, luaL_Buffer *B, size_t sz);
|
||||
|
||||
#define luaL_prepbuffer(B) luaL_prepbuffsize(B, LUAL_BUFFERSIZE)
|
||||
|
||||
/* }====================================================== */
|
||||
|
||||
|
||||
49
lstrlib.c
49
lstrlib.c
@ -1,5 +1,5 @@
|
||||
/*
|
||||
** $Id: lstrlib.c,v 1.147 2009/12/17 12:50:20 roberto Exp roberto $
|
||||
** $Id: lstrlib.c,v 1.148 2010/01/04 16:37:19 roberto Exp roberto $
|
||||
** Standard library for string operations and pattern-matching
|
||||
** See Copyright Notice in lua.h
|
||||
*/
|
||||
@ -65,12 +65,13 @@ static int str_sub (lua_State *L) {
|
||||
|
||||
|
||||
static int str_reverse (lua_State *L) {
|
||||
size_t l;
|
||||
size_t l, i;
|
||||
luaL_Buffer b;
|
||||
const char *s = luaL_checklstring(L, 1, &l);
|
||||
luaL_buffinit(L, &b);
|
||||
while (l--) luaL_addchar(&b, s[l]);
|
||||
luaL_pushresult(&b);
|
||||
char *p = luaL_buffinitsize(L, &b, l);
|
||||
for (i = 0; i < l; i++)
|
||||
p[i] = s[l - i - 1];
|
||||
luaL_pushresultsize(&b, l);
|
||||
return 1;
|
||||
}
|
||||
|
||||
@ -80,10 +81,10 @@ static int str_lower (lua_State *L) {
|
||||
size_t i;
|
||||
luaL_Buffer b;
|
||||
const char *s = luaL_checklstring(L, 1, &l);
|
||||
luaL_buffinit(L, &b);
|
||||
char *p = luaL_buffinitsize(L, &b, l);
|
||||
for (i=0; i<l; i++)
|
||||
luaL_addchar(&b, tolower(uchar(s[i])));
|
||||
luaL_pushresult(&b);
|
||||
p[i] = tolower(uchar(s[i]));
|
||||
luaL_pushresultsize(&b, l);
|
||||
return 1;
|
||||
}
|
||||
|
||||
@ -93,10 +94,10 @@ static int str_upper (lua_State *L) {
|
||||
size_t i;
|
||||
luaL_Buffer b;
|
||||
const char *s = luaL_checklstring(L, 1, &l);
|
||||
luaL_buffinit(L, &b);
|
||||
char *p = luaL_buffinitsize(L, &b, l);
|
||||
for (i=0; i<l; i++)
|
||||
luaL_addchar(&b, toupper(uchar(s[i])));
|
||||
luaL_pushresult(&b);
|
||||
p[i] = toupper(uchar(s[i]));
|
||||
luaL_pushresultsize(&b, l);
|
||||
return 1;
|
||||
}
|
||||
|
||||
@ -136,13 +137,13 @@ static int str_char (lua_State *L) {
|
||||
int n = lua_gettop(L); /* number of arguments */
|
||||
int i;
|
||||
luaL_Buffer b;
|
||||
luaL_buffinit(L, &b);
|
||||
char *p = luaL_buffinitsize(L, &b, n);
|
||||
for (i=1; i<=n; i++) {
|
||||
int c = luaL_checkint(L, i);
|
||||
luaL_argcheck(L, uchar(c) == c, i, "invalid value");
|
||||
luaL_addchar(&b, uchar(c));
|
||||
p[i - 1] = uchar(c);
|
||||
}
|
||||
luaL_pushresult(&b);
|
||||
luaL_pushresultsize(&b, n);
|
||||
return 1;
|
||||
}
|
||||
|
||||
@ -773,6 +774,9 @@ static const char *scanformat (lua_State *L, const char *strfrmt, char *form) {
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
** add length modifier into integer formats
|
||||
*/
|
||||
static void addintlen (char *form) {
|
||||
size_t l = strlen(form);
|
||||
char spec = form[l - 1];
|
||||
@ -796,12 +800,13 @@ static int str_format (lua_State *L) {
|
||||
luaL_addchar(&b, *strfrmt++); /* %% */
|
||||
else { /* format item */
|
||||
char form[MAX_FORMAT]; /* to store the format (`%...') */
|
||||
char buff[MAX_ITEM]; /* to store the formatted item */
|
||||
char *buff = luaL_prepbuffsize(&b, MAX_ITEM); /* to put formatted item */
|
||||
int nb = 0; /* number of bytes in added item */
|
||||
arg++;
|
||||
strfrmt = scanformat(L, strfrmt, form);
|
||||
switch (*strfrmt++) {
|
||||
case 'c': {
|
||||
sprintf(buff, form, luaL_checkint(L, arg));
|
||||
nb = sprintf(buff, form, luaL_checkint(L, arg));
|
||||
break;
|
||||
}
|
||||
case 'd': case 'i':
|
||||
@ -810,17 +815,17 @@ static int str_format (lua_State *L) {
|
||||
LUA_INTFRM_T r = (n < 0) ? (LUA_INTFRM_T)n :
|
||||
(LUA_INTFRM_T)(unsigned LUA_INTFRM_T)n;
|
||||
addintlen(form);
|
||||
sprintf(buff, form, r);
|
||||
nb = sprintf(buff, form, r);
|
||||
break;
|
||||
}
|
||||
case 'e': case 'E': case 'f':
|
||||
case 'g': case 'G': {
|
||||
sprintf(buff, form, (double)luaL_checknumber(L, arg));
|
||||
nb = sprintf(buff, form, (double)luaL_checknumber(L, arg));
|
||||
break;
|
||||
}
|
||||
case 'q': {
|
||||
addquoted(L, &b, arg);
|
||||
continue; /* skip the 'addsize' at the end */
|
||||
break;
|
||||
}
|
||||
case 's': {
|
||||
size_t l;
|
||||
@ -830,10 +835,10 @@ static int str_format (lua_State *L) {
|
||||
keep original string */
|
||||
lua_pushvalue(L, arg);
|
||||
luaL_addvalue(&b);
|
||||
continue; /* skip the `addsize' at the end */
|
||||
break;
|
||||
}
|
||||
else {
|
||||
sprintf(buff, form, s);
|
||||
nb = sprintf(buff, form, s);
|
||||
break;
|
||||
}
|
||||
}
|
||||
@ -842,7 +847,7 @@ static int str_format (lua_State *L) {
|
||||
LUA_QL("format"), *(strfrmt - 1));
|
||||
}
|
||||
}
|
||||
luaL_addlstring(&b, buff, strlen(buff));
|
||||
luaL_addsize(&b, nb);
|
||||
}
|
||||
}
|
||||
luaL_pushresult(&b);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user