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Improve handling of zero bytes in input files 

This is certainly a corner case, but GCC and clang both accept zero
bytes at least in comments, and SWIG's current handling is to ignore
the zero byte and all following characters up to and including the next
newline, so for example if a // comment contains a zero byte SWIG would
quietly ignore the next line.

Closes #3010
This commit is contained in:
Olly Betts 2024-08-15 16:40:46 +12:00
parent 9a12b0e5bc
commit 30030583da
10 changed files with 92 additions and 78 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

8
CHANGES.current
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@ -7,6 +7,14 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
Version 4.3.0 (in progress)
===========================
2024-09-03: olly
#3010 Improve handling of zero bytes in input files. This is
certainly a corner case, but GCC and clang both accept zero bytes
at least in comments, and SWIG's current handling is to ignore
the zero byte and all following characters up to and including the
next newline, so for example if a // comment contains a zero byte
SWIG would quietly ignore the next line.
2024-08-30: olly
#2996 Fix generic string literal handling to handle embedded zero
bytes. This allows such strings to work for C# (with %csconst), D

BIN
Examples/test-suite/errors/pp_zerobyte.i Normal file
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Binary file not shown.

5
Examples/test-suite/errors/pp_zerobyte.stderr Normal file
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@ -0,0 +1,5 @@
pp_zerobyte.i:6: Error: CPP #error "case 1a". Use the -cpperraswarn option to continue swig processing.
pp_zerobyte.i:7: Error: CPP #error "case 1b". Use the -cpperraswarn option to continue swig processing.
pp_zerobyte.i:9: Error: CPP #error "case 2a". Use the -cpperraswarn option to continue swig processing.
pp_zerobyte.i:10: Error: CPP #error "case 2b". Use the -cpperraswarn option to continue swig processing.
pp_zerobyte.i:14: Error: CPP #error "case 3". Use the -cpperraswarn option to continue swig processing.

2
Source/CParse/cparse.h
View File

@ -43,7 +43,7 @@ extern "C" {
extern void scanner_set_main_input_file(String *file);
extern String *scanner_get_main_input_file(void);
extern void Swig_cparse_follow_locators(int);
extern void start_inline(char *, int);
extern void scanner_start_inline(String *, int);
extern String *scanner_ccode;
extern int yylex(void);

6
Source/CParse/cscanner.c
View File

@ -141,14 +141,14 @@ void scanner_file(DOHFile * f) {
}
/* ----------------------------------------------------------------------------
* start_inline(char *text, int line)
* scanner_start_inline(String *text, int line)
*
* Take a chunk of text and recursively feed it back into the scanner. Used
* by the %inline directive.
* ------------------------------------------------------------------------- */
void start_inline(char *text, int line) {
String *stext = NewString(text);
void scanner_start_inline(String *text, int line) {
String *stext = Copy(text);
Seek(stext,0,SEEK_SET);
Setfile(stext,cparse_file);

4
Source/CParse/parser.y
View File

@ -2317,7 +2317,7 @@ inline_directive : INLINE HBLOCK {
Setline($HBLOCK,cparse_start_line);
Setfile($HBLOCK,cparse_file);
cpps = Preprocessor_parse($HBLOCK);
start_inline(Char(cpps), cparse_start_line);
scanner_start_inline(cpps, cparse_start_line);
Delete($HBLOCK);
Delete(cpps);
}
@ -2341,7 +2341,7 @@ inline_directive : INLINE HBLOCK {
Setattr($$,"code", code);
Delete(code);
cpps=Copy(scanner_ccode);
start_inline(Char(cpps), start_line);
scanner_start_inline(cpps, start_line);
Delete(cpps);
}
}

2
Source/DOH/string.c
View File

@ -1230,7 +1230,7 @@ DOHString *DohNewStringWithSize(const DOHString_or_char *so, int len) {
str->str = (char *) DohMalloc(max);
str->maxsize = max;
if (s) {
strncpy(str->str, s, len);
memcpy(str->str, s, len);
str->str[l] = 0;
str->len = l;
str->sp = l;

7
Source/Preprocessor/cpp.c
View File

@ -1419,11 +1419,10 @@ static void addline(DOH *s1, DOH *s2, int allow) {
if (allow) {
Append(s1, s2);
} else {
char *c = Char(s2);
while (*c) {
if (*c == '\n')
int len = Len(s2);
for (int i = 0; i < len; ++i) {
if (Char(s2)[i] == '\n')
Putc('\n', s1);
c++;
}
}
}

6
Source/Swig/include.c
View File

@ -224,8 +224,10 @@ String *Swig_read_file(FILE *f) {
String *str = NewStringEmpty();
assert(str);
while (fgets(buffer, 4095, f)) {
Append(str, buffer);
while (1) {
size_t c = fread(buffer, 1, sizeof(buffer), f);
if (c > 0) Write(str, buffer, c);
if (c < sizeof(buffer)) break;
}
len = Len(str);
/* Add a newline if not present on last line -- the preprocessor seems to

130
Source/Swig/scanner.c
View File

@ -209,26 +209,26 @@ void Scanner_idstart(Scanner *s, const char *id) {
/* -----------------------------------------------------------------------------
* nextchar()
*
* Returns the next character from the scanner or 0 if end of the string.
* Returns the next character from the scanner or EOF if end of the string.
* ----------------------------------------------------------------------------- */
static char nextchar(Scanner *s) {
static int nextchar(Scanner *s) {
int nc;
if (!s->str)
return 0;
return EOF;
while ((nc = Getc(s->str)) == EOF) {
Delete(s->str);
s->str = 0;
Delitem(s->scanobjs, 0);
if (Len(s->scanobjs) == 0)
return 0;
return EOF;
s->str = Getitem(s->scanobjs, 0);
s->line = Getline(s->str);
DohIncref(s->str);
}
if ((nc == '\n') && (!s->freeze_line))
s->line++;
Putc(nc,s->text);
return (char)nc;
Putc(nc, s->text);
return nc;
}
/* -----------------------------------------------------------------------------
@ -397,7 +397,7 @@ static void get_escape(Scanner *s) {
while (1) {
c = nextchar(s);
if (c == 0)
if (c == EOF)
break;
switch (state) {
case 0:
@ -530,7 +530,7 @@ static int look(Scanner *s) {
while (1) {
switch (state) {
case 0:
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return (0);
/* Process delimiters */
@ -547,7 +547,7 @@ static int look(Scanner *s) {
break;
case 1000:
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return (0);
if (c == '%')
state = 4; /* Possibly a SWIG directive */
@ -652,7 +652,7 @@ static int look(Scanner *s) {
break;
case 1: /* Comment block */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return (0);
if (c == '/') {
state = 10; /* C++ style comment */
@ -674,7 +674,7 @@ static int look(Scanner *s) {
}
break;
case 10: /* C++ style comment */
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
Swig_error(cparse_file, cparse_start_line, "Unterminated comment\n");
return SWIG_TOKEN_ERROR;
}
@ -686,7 +686,7 @@ static int look(Scanner *s) {
}
break;
case 11: /* C style comment block */
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
Swig_error(cparse_file, cparse_start_line, "Unterminated comment\n");
return SWIG_TOKEN_ERROR;
}
@ -697,7 +697,7 @@ static int look(Scanner *s) {
}
break;
case 12: /* Still in C style comment */
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
Swig_error(cparse_file, cparse_start_line, "Unterminated comment\n");
return SWIG_TOKEN_ERROR;
}
@ -716,7 +716,7 @@ static int look(Scanner *s) {
break;
}
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
Swig_error(cparse_file, cparse_start_line, "Unterminated string\n");
return SWIG_TOKEN_ERROR;
}
@ -730,7 +730,7 @@ static int look(Scanner *s) {
break;
case 20: /* Inside the string */
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
Swig_error(cparse_file, cparse_start_line, "Unterminated string\n");
return SWIG_TOKEN_ERROR;
}
@ -747,7 +747,7 @@ static int look(Scanner *s) {
if (c==')') {
int i=0;
String *end_delimiter = NewStringEmpty();
while ((c = nextchar(s)) != 0 && c!='\"') {
while ((c = nextchar(s)) != EOF && c != '\"') {
Putc( (char)c, end_delimiter );
i++;
}
@ -761,7 +761,7 @@ static int look(Scanner *s) {
str_delimiter = 0;
return SWIG_TOKEN_STRING;
} else { /* Incorrect end delimiter occurred */
if (c == 0) {
if (c == EOF) {
Swig_error(cparse_file, cparse_start_line, "Unterminated raw string, started with R\"%s( is not terminated by )%s\"\n", str_delimiter, str_delimiter);
return SWIG_TOKEN_ERROR;
}
@ -774,7 +774,7 @@ static int look(Scanner *s) {
break;
case 3: /* Maybe a not equals */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_LNOT;
else if (c == '=')
return SWIG_TOKEN_NOTEQUAL;
@ -785,7 +785,7 @@ static int look(Scanner *s) {
break;
case 31: /* AND or Logical AND or ANDEQUAL */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_AND;
else if (c == '&')
return SWIG_TOKEN_LAND;
@ -798,7 +798,7 @@ static int look(Scanner *s) {
break;
case 32: /* OR or Logical OR */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_OR;
else if (c == '|')
return SWIG_TOKEN_LOR;
@ -811,7 +811,7 @@ static int look(Scanner *s) {
break;
case 33: /* EQUAL or EQUALTO */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_EQUAL;
else if (c == '=')
return SWIG_TOKEN_EQUALTO;
@ -822,7 +822,7 @@ static int look(Scanner *s) {
break;
case 4: /* A wrapper generator directive (maybe) */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_PERCENT;
if (c == '{') {
state = 40; /* Include block */
@ -845,7 +845,7 @@ static int look(Scanner *s) {
break;
case 40: /* Process an include block */
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
Swig_error(cparse_file, cparse_start_line, "Unterminated block\n");
return SWIG_TOKEN_ERROR;
}
@ -853,7 +853,7 @@ static int look(Scanner *s) {
state = 41;
break;
case 41: /* Still processing include block */
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
set_error(s,s->start_line,"Unterminated code block");
return 0;
}
@ -869,7 +869,7 @@ static int look(Scanner *s) {
case 5: /* Maybe a double colon */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_COLON;
if (c == ':')
state = 50;
@ -880,7 +880,7 @@ static int look(Scanner *s) {
break;
case 50: /* DCOLON, DCOLONSTAR */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_DCOLON;
else if (c == '*')
return SWIG_TOKEN_DCOLONSTAR;
@ -891,14 +891,14 @@ static int look(Scanner *s) {
break;
case 60: /* shift operators */
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
brackets_increment(s);
return SWIG_TOKEN_LESSTHAN;
}
if (c == '<')
state = 240;
else if (c == '=') {
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
return SWIG_TOKEN_LTEQUAL;
} else if (c == '>' && cparse_cplusplus) { /* Spaceship operator */
return SWIG_TOKEN_LTEQUALGT;
@ -913,7 +913,7 @@ static int look(Scanner *s) {
}
break;
case 61:
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
brackets_decrement(s);
return SWIG_TOKEN_GREATERTHAN;
}
@ -942,7 +942,7 @@ static int look(Scanner *s) {
break;
}
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
state = 76;
}
else if (c == '\"') { /* Definitely u, U or L string */
@ -966,7 +966,7 @@ static int look(Scanner *s) {
break;
case 70: /* Identifier */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
state = 76;
else if (isalnum(c) || (c == '_') || (c == '$')) {
state = 70;
@ -977,7 +977,7 @@ static int look(Scanner *s) {
break;
case 71: /* Possibly u8 string/char */
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
state = 76;
}
else if (c=='\"') {
@ -1001,7 +1001,7 @@ static int look(Scanner *s) {
case 72: /* Possibly CUSTOM DELIMITER string */
case 73:
case 74:
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
state = 76;
}
else if (c=='\"') {
@ -1025,7 +1025,7 @@ static int look(Scanner *s) {
break;
case 75: /* Special identifier $ */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_DOLLAR;
if (isalnum(c) || (c == '_') || (c == '*') || (c == '&')) {
state = 70;
@ -1069,7 +1069,7 @@ static int look(Scanner *s) {
return SWIG_TOKEN_ID;
case 77: /*identifier or wide string literal*/
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_ID;
else if (c == '\"') {
s->start_line = s->line;
@ -1090,7 +1090,7 @@ static int look(Scanner *s) {
break;
case 78: /* Processing a wide string literal*/
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
Swig_error(cparse_file, cparse_start_line, "Unterminated wide string\n");
return SWIG_TOKEN_ERROR;
}
@ -1104,7 +1104,7 @@ static int look(Scanner *s) {
break;
case 79: /* Processing a wide char literal */
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
Swig_error(cparse_file, cparse_start_line, "Unterminated wide character constant\n");
return SWIG_TOKEN_ERROR;
}
@ -1118,7 +1118,7 @@ static int look(Scanner *s) {
break;
case 8: /* A numerical digit */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_INT;
if (c == '.') {
state = 81;
@ -1138,7 +1138,7 @@ static int look(Scanner *s) {
}
break;
case 81: /* A floating pointer number of some sort */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_DOUBLE;
if (isdigit(c))
state = 81;
@ -1155,7 +1155,7 @@ static int look(Scanner *s) {
}
break;
case 82:
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
Swig_error(cparse_file, cparse_start_line, "Exponent does not have any digits\n");
return SWIG_TOKEN_ERROR;
}
@ -1169,7 +1169,7 @@ static int look(Scanner *s) {
break;
case 820:
/* Like case 82, but we've seen a decimal point. */
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
Swig_error(cparse_file, cparse_start_line, "Exponent does not have any digits\n");
return SWIG_TOKEN_ERROR;
}
@ -1183,7 +1183,7 @@ static int look(Scanner *s) {
break;
case 83:
/* Might be a hexadecimal, octal or binary number */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_INT;
if (isdigit(c))
state = 84;
@ -1209,7 +1209,7 @@ static int look(Scanner *s) {
if (c == '8' || c == '9') {
Swig_error(Scanner_file(s), Scanner_line(s), "Invalid digit '%c' in octal constant\n", c);
}
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_INT;
if (isdigit(c))
state = 84;
@ -1228,7 +1228,7 @@ static int look(Scanner *s) {
break;
case 85:
/* This is an hex number */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_INT;
if (isxdigit(c))
state = 85;
@ -1247,7 +1247,7 @@ static int look(Scanner *s) {
break;
case 850:
/* This is a binary number */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_INT;
if ((c == '0') || (c == '1'))
state = 850;
@ -1264,7 +1264,7 @@ static int look(Scanner *s) {
break;
case 860:
/* hexadecimal float */
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
Swig_error(cparse_file, cparse_start_line, "Hexadecimal floating literals require an exponent\n");
return SWIG_TOKEN_ERROR;
}
@ -1281,7 +1281,7 @@ static int look(Scanner *s) {
case 86:
/* Rest of floating point number */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_DOUBLE;
if (isdigit(c))
state = 86;
@ -1298,7 +1298,7 @@ static int look(Scanner *s) {
case 87:
/* A long integer of some sort */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_LONG;
if ((c == 'u') || (c == 'U')) {
return SWIG_TOKEN_ULONG;
@ -1313,7 +1313,7 @@ static int look(Scanner *s) {
/* A long long integer */
case 870:
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_LONGLONG;
if ((c == 'u') || (c == 'U')) {
return SWIG_TOKEN_ULONGLONG;
@ -1325,7 +1325,7 @@ static int look(Scanner *s) {
/* An unsigned number */
case 88:
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_UINT;
if ((c == 'l') || (c == 'L')) {
state = 880;
@ -1337,7 +1337,7 @@ static int look(Scanner *s) {
/* Possibly an unsigned long long or unsigned long */
case 880:
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_ULONG;
if ((c == 'l') || (c == 'L'))
return SWIG_TOKEN_ULONGLONG;
@ -1348,7 +1348,7 @@ static int look(Scanner *s) {
/* A character constant */
case 9:
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
Swig_error(cparse_file, cparse_start_line, "Unterminated character constant\n");
return SWIG_TOKEN_ERROR;
}
@ -1364,7 +1364,7 @@ static int look(Scanner *s) {
/* A period or an ellipsis or maybe a floating point number */
case 100:
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return (0);
if (isdigit(c))
state = 81;
@ -1379,7 +1379,7 @@ static int look(Scanner *s) {
/* An ellipsis */
case 101:
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return (0);
if (c == '.') {
return SWIG_TOKEN_ELLIPSIS;
@ -1392,7 +1392,7 @@ static int look(Scanner *s) {
/* A left bracket or a double left bracket */
case 102:
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
return SWIG_TOKEN_LBRACKET;
} else if (c == '[') {
return SWIG_TOKEN_LLBRACKET;
@ -1404,7 +1404,7 @@ static int look(Scanner *s) {
/* a right bracket or a double right bracket */
case 103:
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
return SWIG_TOKEN_RBRACKET;
} else if (c == ']') {
return SWIG_TOKEN_RRBRACKET;
@ -1415,7 +1415,7 @@ static int look(Scanner *s) {
break;
case 200: /* PLUS, PLUSPLUS, PLUSEQUAL */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_PLUS;
else if (c == '+')
return SWIG_TOKEN_PLUSPLUS;
@ -1428,7 +1428,7 @@ static int look(Scanner *s) {
break;
case 210: /* MINUS, MINUSMINUS, MINUSEQUAL, ARROW */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_MINUS;
else if (c == '-')
return SWIG_TOKEN_MINUSMINUS;
@ -1443,7 +1443,7 @@ static int look(Scanner *s) {
break;
case 211: /* ARROW, ARROWSTAR */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_ARROW;
else if (c == '*')
return SWIG_TOKEN_ARROWSTAR;
@ -1455,7 +1455,7 @@ static int look(Scanner *s) {
case 220: /* STAR, TIMESEQUAL */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_STAR;
else if (c == '=')
return SWIG_TOKEN_TIMESEQUAL;
@ -1466,7 +1466,7 @@ static int look(Scanner *s) {
break;
case 230: /* XOR, XOREQUAL */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_XOR;
else if (c == '=')
return SWIG_TOKEN_XOREQUAL;
@ -1477,7 +1477,7 @@ static int look(Scanner *s) {
break;
case 240: /* LSHIFT, LSEQUAL */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_LSHIFT;
else if (c == '=')
return SWIG_TOKEN_LSEQUAL;
@ -1488,7 +1488,7 @@ static int look(Scanner *s) {
break;
case 250: /* RSHIFT, RSEQUAL */
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return SWIG_TOKEN_RSHIFT;
else if (c == '=')
return SWIG_TOKEN_RSEQUAL;
@ -1500,7 +1500,7 @@ static int look(Scanner *s) {
/* Reverse string */
case 900:
if ((c = nextchar(s)) == 0) {
if ((c = nextchar(s)) == EOF) {
Swig_error(cparse_file, cparse_start_line, "Unterminated character constant\n");
return SWIG_TOKEN_ERROR;
}
@ -1564,7 +1564,7 @@ void Scanner_skip_line(Scanner *s) {
Setfile(s->text, Getfile(s->str));
Setline(s->text, s->line);
while (!done) {
if ((c = nextchar(s)) == 0)
if ((c = nextchar(s)) == EOF)
return;
if (c == '\\') {
nextchar(s);