commit 889284ebd01dbc923403b0aa38b82dc80ed86af8
parent 6956331093e3a8d21c795b3bb125594b8ed6617b
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Mon, 18 May 2009 14:27:40 -0300
hexadecimal escape sequences in strings + better error messages for
bad decimal escape sequences
Diffstat:
M | llex.c | | | 77 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++---------------------- |
1 file changed, 55 insertions(+), 22 deletions(-)
diff --git a/llex.c b/llex.c
@@ -1,5 +1,5 @@
/*
-** $Id: llex.c,v 2.31 2009/02/19 17:18:25 roberto Exp roberto $
+** $Id: llex.c,v 2.32 2009/03/11 13:27:32 roberto Exp roberto $
** Lexical Analyzer
** See Copyright Notice in lua.h
*/
@@ -29,7 +29,6 @@
-
#define currIsNewline(ls) (ls->current == '\n' || ls->current == '\r')
@@ -52,14 +51,14 @@ static void lexerror (LexState *ls, const char *msg, int token);
static void save (LexState *ls, int c) {
Mbuffer *b = ls->buff;
- if (b->n + 1 > b->buffsize) {
+ if (luaZ_bufflen(b) + 1 > luaZ_sizebuffer(b)) {
size_t newsize;
- if (b->buffsize >= MAX_SIZET/2)
+ if (luaZ_sizebuffer(b) >= MAX_SIZET/2)
lexerror(ls, "lexical element too long", 0);
- newsize = b->buffsize * 2;
+ newsize = luaZ_sizebuffer(b) * 2;
luaZ_resizebuffer(ls->L, b, newsize);
}
- b->buffer[b->n++] = cast(char, c);
+ b->buffer[luaZ_bufflen(b)++] = cast(char, c);
}
@@ -264,6 +263,48 @@ static void read_long_string (LexState *ls, SemInfo *seminfo, int sep) {
}
+static int hexavalue (int c) {
+ if (lisdigit(c)) return c - '0';
+ else if (lisupper(c)) return c - 'A' + 10;
+ else return c - 'a' + 10;
+}
+
+
+static int readhexaesc (LexState *ls) {
+ int c1, c2 = EOZ;
+ if (!lisxdigit(c1 = next(ls)) || !lisxdigit(c2 = next(ls))) {
+ luaZ_resetbuffer(ls->buff); /* prepare error message */
+ save(ls, '\\'); save(ls, 'x');
+ if (c1 != EOZ) save(ls, c1);
+ if (c2 != EOZ) save(ls, c2);
+ lexerror(ls, "hexadecimal digit expected", TK_STRING);
+ }
+ return (hexavalue(c1) << 4) + hexavalue(c2);
+}
+
+
+static int readdecesc (LexState *ls) {
+ int c1 = ls->current, c2, c3;
+ int c = c1 - '0';
+ if (lisdigit(c2 = next(ls))) {
+ c = 10*c + c2 - '0';
+ if (lisdigit(c3 = next(ls))) {
+ c = 10*c + c3 - '0';
+ if (c > UCHAR_MAX) {
+ luaZ_resetbuffer(ls->buff); /* prepare error message */
+ save(ls, '\\');
+ save(ls, c1); save(ls, c2); save(ls, c3);
+ lexerror(ls, "decimal escape too large", TK_STRING);
+ }
+ return c;
+ }
+ }
+ /* else, has read one character that was not a digit */
+ zungetc(ls->z); /* return it to input stream */
+ return c;
+}
+
+
static void read_string (LexState *ls, int del, SemInfo *seminfo) {
save_and_next(ls);
while (ls->current != del) {
@@ -275,8 +316,8 @@ static void read_string (LexState *ls, int del, SemInfo *seminfo) {
case '\r':
lexerror(ls, "unfinished string", TK_STRING);
continue; /* to avoid warnings */
- case '\\': {
- int c;
+ case '\\': { /* escape sequences */
+ int c; /* final character to be saved */
next(ls); /* do not save the `\' */
switch (ls->current) {
case 'a': c = '\a'; break;
@@ -286,28 +327,20 @@ static void read_string (LexState *ls, int del, SemInfo *seminfo) {
case 'r': c = '\r'; break;
case 't': c = '\t'; break;
case 'v': c = '\v'; break;
+ case 'x': c = readhexaesc(ls); break;
case '\n':
case '\r': save(ls, '\n'); inclinenumber(ls); continue;
case EOZ: continue; /* will raise an error next loop */
default: {
if (!lisdigit(ls->current))
- save_and_next(ls); /* handles \\, \", \', and \? */
- else { /* \xxx */
- int i = 0;
- c = 0;
- do {
- c = 10*c + (ls->current-'0');
- next(ls);
- } while (++i<3 && lisdigit(ls->current));
- if (c > UCHAR_MAX)
- lexerror(ls, "escape sequence too large", TK_STRING);
- save(ls, c);
- }
- continue;
+ c = ls->current; /* handles \\, \", \', and \? */
+ else /* digital escape \ddd */
+ c = readdecesc(ls);
+ break;
}
}
- save(ls, c);
next(ls);
+ save(ls, c);
continue;
}
default: