Fixed C++98 lexer example (program code).

Fix: check length when parsing integer sequences.
If a string contains e.g. "\uFFFFf", it must be recognized as "\xffff\x66"
and not as "\xfffff".

diff --git a/src/examples/07_c++98.re b/src/examples/07_c++98.re
index 36a685ba761710366ad5b65ccbaae999bb45b646..2be8488ce30a29612e7465221d696468a86347c2 100644 (file)
--- a/src/examples/07_c++98.re
+++ b/src/examples/07_c++98.re
@@ -61,54 +61,45 @@ static bool adddgt(unsigned long &u, unsigned long d)
     return true;
 }
 
-static bool lex_int_sfx(const unsigned char *s, unsigned long u)
+static bool lex_oct(const unsigned char *s, const unsigned char *e, unsigned long &u)
 {
+    for (u = 0, ++s; s < e;) {
     /*!re2c
         re2c:yyfill:enable = 0;
         re2c:define:YYCURSOR = s;
-        *           { return u < INT_MAX; }
-        'u'         { return u < UINT_MAX; }
-        'l'         { return u < LONG_MAX; }
-        'ul' | 'lu' { return true; }
-    */
-}
-
-static bool lex_oct(const unsigned char *s, bool sfx, unsigned long &u)
-{
-    for (u = 0, ++s;;) {
-    /*!re2c
-        re2c:yyfill:enable = 0;
-        re2c:define:YYCURSOR = s;
-        [0-7] { if (adddgt<8>(u, s[-1] - 0x30u)) continue; return false; }
-        ""    { return !sfx || lex_int_sfx(s, u); }
+        [0-7] { if (!adddgt<8>(u, s[-1] - 0x30u)) return false; continue; }
+        *     { return false; }
     */
     }
+    return true;
 }
 
-static bool lex_dec(const unsigned char *s, bool sfx, unsigned long &u)
+static bool lex_dec(const unsigned char *s, const unsigned char *e, unsigned long &u)
 {
-    for (u = 0;;) {
+    for (u = 0; s < e;) {
     /*!re2c
         re2c:yyfill:enable = 0;
         re2c:define:YYCURSOR = s;
-        [0-9] { if (adddgt<10>(u, s[-1] - 0x30u)) continue; return false; }
-        ""    { return !sfx || lex_int_sfx(s, u); }
+        [0-9] { if (!adddgt<10>(u, s[-1] - 0x30u)) return false; continue; }
+        *     { return false; }
     */
     }
+    return true;
 }
 
-static bool lex_hex(const unsigned char *s, bool sfx, unsigned long &u)
+static bool lex_hex(const unsigned char *s, const unsigned char *e, unsigned long &u)
 {
-    for (u = 0, s += 2;;) {
+    for (u = 0, s += 2; s < e;) {
     /*!re2c
         re2c:yyfill:enable = 0;
         re2c:define:YYCURSOR = s;
-        [0-9] { if (adddgt<16>(u, s[-1] - 0x30u))      continue; return false; }
-        [a-f] { if (adddgt<16>(u, s[-1] - 0x61u + 10)) continue; return false; }
-        [A-F] { if (adddgt<16>(u, s[-1] - 0x41u + 10)) continue; return false; }
-        ""    { return !sfx || lex_int_sfx(s, u); }
+        [0-9] { if (!adddgt<16>(u, s[-1] - 0x30u))      return false; continue; }
+        [a-f] { if (!adddgt<16>(u, s[-1] - 0x61u + 10)) return false; continue; }
+        [A-F] { if (!adddgt<16>(u, s[-1] - 0x41u + 10)) return false; continue; }
+        *     { return false; }
     */
     }
+    return true;
 }
 
 static bool lex_str(input_t &in, unsigned char q)
@@ -136,10 +127,10 @@ static bool lex_str(input_t &in, unsigned char q)
             "\\'"                { u = '\''; continue; }
             "\\\""               { u = '"';  continue; }
             "\\?"                { u = '?';  continue; }
-            "\\" [0-7]{1,3}      { lex_oct(in.tok, false, u); continue; }
-            "\\u" [0-9a-fA-F]{4} { lex_hex(in.tok, false, u); continue; }
-            "\\U" [0-9a-fA-F]{8} { lex_hex(in.tok, false, u); continue; }
-            "\\x" [0-9a-fA-F]+   { if (!lex_hex(in.tok, false, u)) return false; continue; }
+            "\\" [0-7]{1,3}      { lex_oct(in.tok, in.cur, u); continue; }
+            "\\u" [0-9a-fA-F]{4} { lex_hex(in.tok, in.cur, u); continue; }
+            "\\U" [0-9a-fA-F]{8} { lex_hex(in.tok, in.cur, u); continue; }
+            "\\x" [0-9a-fA-F]+   { if (!lex_hex(in.tok, in.cur, u)) return false; continue; }
         */
     }
     printf("%c", q);
@@ -220,13 +211,12 @@ static bool lex(input_t &in)
             "L"? "''" { return false; }
 
             // integer literals
-            int_sfx = 'u' | 'l' | 'ul' | 'lu';
-            oct = "0" [0-7]*        int_sfx?;
-            dec = [1-9][0-9]*       int_sfx?;
-            hex = '0x' [0-9a-fA-F]+ int_sfx?;
-            oct { if (!lex_oct(in.tok, true, u)) return false; printf("%lu", u); continue; }
-            dec { if (!lex_dec(in.tok, true, u)) return false; printf("%lu", u); continue; }
-            hex { if (!lex_hex(in.tok, true, u)) return false; printf("%lu", u); continue; }
+            oct = "0" [0-7]*;
+            dec = [1-9][0-9]*;
+            hex = '0x' [0-9a-fA-F]+;
+            oct { if (!lex_oct(in.tok, in.cur, u)) return false; goto sfx; }
+            dec { if (!lex_dec(in.tok, in.cur, u)) return false; goto sfx; }
+            hex { if (!lex_hex(in.tok, in.cur, u)) return false; goto sfx; }
 
             // floating literals
             frc = [0-9]* "." [0-9]+ | [0-9]+ ".";
@@ -356,6 +346,13 @@ static bool lex(input_t &in)
             id = [a-zA-Z_][a-zA-Z_0-9]*;
             id { printf("%.*s", in.cur - in.tok, in.tok); continue; }
         */
+sfx:
+        /*!re2c
+            ""          { if (u > INT_MAX)  return false; printf("%d",  static_cast<int>(u));      continue; }
+            'u'         { if (u > UINT_MAX) return false; printf("%u",  static_cast<unsigned>(u)); continue; }
+            'l'         { if (u > LONG_MAX) return false; printf("%ld", static_cast<long>(u));     continue; }
+            'ul' | 'lu' { printf("%lu", u); continue; }
+        */
     }
 }
 

diff --git a/src/examples/example_07.rst b/src/examples/example_07.rst
index 8b1686ad8f0573f5a5207370d33fd92ebac22ed7..14fbf50923083359ba379484d06c605ce22fe868 100644 (file)
--- a/src/examples/example_07.rst
+++ b/src/examples/example_07.rst
@@ -52,22 +52,23 @@ Generate, compile and run:
      eof = true; memset(lim, 0, YYMAXFILL); lim += YYMAXFILL; } RETURN true; } }; TE
     MPLATE<INT base> STATIC BOOL adddgt(UNSIGNED LONG &u, UNSIGNED LONG d) { IF (u >
      (ULONG_MAX - d) / base) { RETURN false; } u = u * base + d; RETURN true; } STAT
-    IC BOOL lex_int_sfx(CONST UNSIGNED CHAR *s, UNSIGNED LONG u) { } STATIC BOOL lex
-    _oct(CONST UNSIGNED CHAR *s, BOOL sfx, UNSIGNED LONG &u) { FOR (u = 0, ++s;;) { 
-    } } STATIC BOOL lex_dec(CONST UNSIGNED CHAR *s, BOOL sfx, UNSIGNED LONG &u) { FO
-    R (u = 0;;) { } } STATIC BOOL lex_hex(CONST UNSIGNED CHAR *s, BOOL sfx, UNSIGNED
-     LONG &u) { FOR (u = 0, s += 2;;) { } } STATIC BOOL lex_str(input_t &in, UNSIGNE
-    D CHAR q) { printf("\x25\x63", q); FOR (UNSIGNED LONG u = q;; printf("\x5c\x78\x
-    25\x6c\x78", u)) { in.tok = in.cur; } printf("\x25\x63", q); RETURN true; } STAT
-    IC BOOL lex_flt(CONST UNSIGNED CHAR *s) { DOUBLE d = 0; DOUBLE x = 1; INT e = 0;
-     mant_int: mant_frac: exp_sign: exp: sfx: end: printf("\x25\x67", d); RETURN tru
-    e; } STATIC BOOL lex(input_t &in) { UNSIGNED LONG u; FOR (;;) { in.tok = in.cur;
-     } } INT main(INT argc, CHAR **argv) { IF (argc != 2) { printf ("\x75\x73\x61\x6
-    7\x65\x3a\x20\x2e\x2f\x65\x78\x61\x6d\x70\x6c\x65\x20\x3c\x66\x69\x6c\x65\x6e\x6
-    1\x6d\x65\x3e\xa"); RETURN 1; } FILE *file = fopen(argv[1], "\x72\x62"); IF (!fi
-    le) { printf("\x65\x72\x72\x6f\x72\x3a\x20\x63\x61\x6e\x6e\x6f\x74\x20\x6f\x70\x
-    65\x6e\x20\x66\x69\x6c\x65\x3a\x20\x25\x73\xa", argv[1]); RETURN 1; } input_t in
-    (file); IF (!lex(in)) { printf("\x2e\x2e\x2e\x20\x65\x72\x72\x6f\x72\xa"); } ELS
-    E { printf("\xa"); } fclose(file); RETURN 0; }
+    IC BOOL lex_oct(CONST UNSIGNED CHAR *s, CONST UNSIGNED CHAR *e, UNSIGNED LONG &u
+    ) { FOR (u = 0, ++s; s < e;) { } RETURN true; } STATIC BOOL lex_dec(CONST UNSIGN
+    ED CHAR *s, CONST UNSIGNED CHAR *e, UNSIGNED LONG &u) { FOR (u = 0; s < e;) { } 
+    RETURN true; } STATIC BOOL lex_hex(CONST UNSIGNED CHAR *s, CONST UNSIGNED CHAR *
+    e, UNSIGNED LONG &u) { FOR (u = 0, s += 2; s < e;) { } RETURN true; } STATIC BOO
+    L lex_str(input_t &in, UNSIGNED CHAR q) { printf("\x25\x63", q); FOR (UNSIGNED L
+    ONG u = q;; printf("\x5c\x78\x25\x6c\x78", u)) { in.tok = in.cur; } printf("\x25
+    \x63", q); RETURN true; } STATIC BOOL lex_flt(CONST UNSIGNED CHAR *s) { DOUBLE d
+     = 0; DOUBLE x = 1; INT e = 0; mant_int: mant_frac: exp_sign: exp: sfx: end: pri
+    ntf("\x25\x67", d); RETURN true; } STATIC BOOL lex(input_t &in) { UNSIGNED LONG 
+    u; FOR (;;) { in.tok = in.cur; sfx: } } INT main(INT argc, CHAR **argv) { IF (ar
+    gc != 2) { printf ("\x75\x73\x61\x67\x65\x3a\x20\x2e\x2f\x65\x78\x61\x6d\x70\x6c
+    \x65\x20\x3c\x66\x69\x6c\x65\x6e\x61\x6d\x65\x3e\xa"); RETURN 1; } FILE *file = 
+    fopen(argv[1], "\x72\x62"); IF (!file) { printf("\x65\x72\x72\x6f\x72\x3a\x20\x6
+    3\x61\x6e\x6e\x6f\x74\x20\x6f\x70\x65\x6e\x20\x66\x69\x6c\x65\x3a\x20\x25\x73\xa
+    ", argv[1]); RETURN 1; } input_t in(file); IF (!lex(in)) { printf("\x2e\x2e\x2e\
+    x20\x65\x72\x72\x6f\x72\xa"); } ELSE { printf("\xa"); } fclose(file); RETURN 0; 
+    }