eBookReaderSwitch/mupdf/source/pdf/pdf-parse.c

720 lines
15 KiB
C

#include "mupdf/fitz.h"
#include "mupdf/pdf.h"
#include <string.h>
fz_rect
pdf_to_rect(fz_context *ctx, pdf_obj *array)
{
if (!pdf_is_array(ctx, array))
return fz_empty_rect;
else
{
float a = pdf_array_get_real(ctx, array, 0);
float b = pdf_array_get_real(ctx, array, 1);
float c = pdf_array_get_real(ctx, array, 2);
float d = pdf_array_get_real(ctx, array, 3);
fz_rect r;
r.x0 = fz_min(a, c);
r.y0 = fz_min(b, d);
r.x1 = fz_max(a, c);
r.y1 = fz_max(b, d);
return r;
}
}
fz_quad
pdf_to_quad(fz_context *ctx, pdf_obj *array, int offset)
{
fz_quad q;
q.ul.x = pdf_array_get_real(ctx, array, offset+0);
q.ul.y = pdf_array_get_real(ctx, array, offset+1);
q.ur.x = pdf_array_get_real(ctx, array, offset+2);
q.ur.y = pdf_array_get_real(ctx, array, offset+3);
q.ll.x = pdf_array_get_real(ctx, array, offset+4);
q.ll.y = pdf_array_get_real(ctx, array, offset+5);
q.lr.x = pdf_array_get_real(ctx, array, offset+6);
q.lr.y = pdf_array_get_real(ctx, array, offset+7);
return q;
}
fz_matrix
pdf_to_matrix(fz_context *ctx, pdf_obj *array)
{
if (!pdf_is_array(ctx, array))
return fz_identity;
else
{
fz_matrix m;
m.a = pdf_array_get_real(ctx, array, 0);
m.b = pdf_array_get_real(ctx, array, 1);
m.c = pdf_array_get_real(ctx, array, 2);
m.d = pdf_array_get_real(ctx, array, 3);
m.e = pdf_array_get_real(ctx, array, 4);
m.f = pdf_array_get_real(ctx, array, 5);
return m;
}
}
static int
rune_from_utf16be(int *out, const unsigned char *s, const unsigned char *end)
{
if (s + 2 <= end)
{
int a = s[0] << 8 | s[1];
if (a >= 0xD800 && a <= 0xDFFF && s + 4 <= end)
{
int b = s[2] << 8 | s[3];
*out = ((a - 0xD800) << 10) + (b - 0xDC00) + 0x10000;
return 4;
}
*out = a;
return 2;
}
*out = FZ_REPLACEMENT_CHARACTER;
return 1;
}
static int
rune_from_utf16le(int *out, const unsigned char *s, const unsigned char *end)
{
if (s + 2 <= end)
{
int a = s[1] << 8 | s[0];
if (a >= 0xD800 && a <= 0xDFFF && s + 4 <= end)
{
int b = s[3] << 8 | s[2];
*out = ((a - 0xD800) << 10) + (b - 0xDC00) + 0x10000;
return 4;
}
*out = a;
return 2;
}
*out = FZ_REPLACEMENT_CHARACTER;
return 1;
}
static size_t
skip_language_code_utf16le(const unsigned char *s, size_t n, size_t i)
{
/* skip language escape codes */
if (i + 6 <= n && s[i+1] == 0 && s[i+0] == 27 && s[i+5] == 0 && s[i+4] == 27)
return 6;
else if (i + 8 <= n && s[i+1] == 0 && s[i+0] == 27 && s[i+7] == 0 && s[i+6] == 27)
return 8;
return 0;
}
static size_t
skip_language_code_utf16be(const unsigned char *s, size_t n, size_t i)
{
/* skip language escape codes */
if (i + 6 <= n && s[i+0] == 0 && s[i+1] == 27 && s[i+4] == 0 && s[i+5] == 27)
return 6;
else if (i + 8 <= n && s[i+0] == 0 && s[i+1] == 27 && s[i+6] == 0 && s[i+7] == 27)
return 8;
return 0;
}
static size_t
skip_language_code_utf8(const unsigned char *s, size_t n, size_t i)
{
/* skip language escape codes */
if (i + 3 <= n && s[i] == 27 && s[i+3])
return 3;
else if (i + 5 <= n && s[i] == 27 && s[i+5] == 27)
return 5;
return 0;
}
/* Convert Unicode/PdfDocEncoding string into utf-8 */
char *
pdf_new_utf8_from_pdf_string(fz_context *ctx, const char *ssrcptr, size_t srclen)
{
const unsigned char *srcptr = (const unsigned char*)ssrcptr;
char *dstptr, *dst;
size_t dstlen = 0;
int ucs;
size_t i, n;
/* UTF-16BE */
if (srclen >= 2 && srcptr[0] == 254 && srcptr[1] == 255)
{
i = 2;
while (i + 2 <= srclen)
{
n = skip_language_code_utf16be(srcptr, srclen, i);
if (n)
i += n;
else
{
i += rune_from_utf16be(&ucs, srcptr + i, srcptr + srclen);
dstlen += fz_runelen(ucs);
}
}
dstptr = dst = fz_malloc(ctx, dstlen + 1);
i = 2;
while (i + 2 <= srclen)
{
n = skip_language_code_utf16be(srcptr, srclen, i);
if (n)
i += n;
else
{
i += rune_from_utf16be(&ucs, srcptr + i, srcptr + srclen);
dstptr += fz_runetochar(dstptr, ucs);
}
}
}
/* UTF-16LE */
else if (srclen >= 2 && srcptr[0] == 255 && srcptr[1] == 254)
{
i = 2;
while (i + 2 <= srclen)
{
n = skip_language_code_utf16le(srcptr, srclen, i);
if (n)
i += n;
else
{
i += rune_from_utf16le(&ucs, srcptr + i, srcptr + srclen);
dstlen += fz_runelen(ucs);
}
}
dstptr = dst = fz_malloc(ctx, dstlen + 1);
i = 2;
while (i + 2 <= srclen)
{
n = skip_language_code_utf16le(srcptr, srclen, i);
if (n)
i += n;
else
{
i += rune_from_utf16le(&ucs, srcptr + i, srcptr + srclen);
dstptr += fz_runetochar(dstptr, ucs);
}
}
}
/* UTF-8 */
else if (srclen >= 3 && srcptr[0] == 239 && srcptr[1] == 187 && srcptr[2] == 191)
{
i = 3;
while (i < srclen)
{
n = skip_language_code_utf8(srcptr, srclen, i);
if (n)
i += n;
else
{
i += 1;
dstlen += 1;
}
}
dstptr = dst = fz_malloc(ctx, dstlen + 1);
i = 3;
while (i < srclen)
{
n = skip_language_code_utf8(srcptr, srclen, i);
if (n)
i += n;
else
*dstptr++ = srcptr[i++];
}
}
/* PDFDocEncoding */
else
{
for (i = 0; i < srclen; i++)
dstlen += fz_runelen(fz_unicode_from_pdf_doc_encoding[srcptr[i]]);
dstptr = dst = fz_malloc(ctx, dstlen + 1);
for (i = 0; i < srclen; i++)
{
ucs = fz_unicode_from_pdf_doc_encoding[srcptr[i]];
dstptr += fz_runetochar(dstptr, ucs);
}
}
*dstptr = 0;
return dst;
}
/* Convert text string object to UTF-8 */
char *
pdf_new_utf8_from_pdf_string_obj(fz_context *ctx, pdf_obj *src)
{
const char *srcptr;
size_t srclen;
srcptr = pdf_to_string(ctx, src, &srclen);
return pdf_new_utf8_from_pdf_string(ctx, srcptr, srclen);
}
/* Load text stream and convert to UTF-8 */
char *
pdf_new_utf8_from_pdf_stream_obj(fz_context *ctx, pdf_obj *src)
{
fz_buffer *stmbuf;
char *srcptr;
size_t srclen;
char *dst = NULL;
stmbuf = pdf_load_stream(ctx, src);
srclen = fz_buffer_storage(ctx, stmbuf, (unsigned char **)&srcptr);
fz_try(ctx)
dst = pdf_new_utf8_from_pdf_string(ctx, srcptr, srclen);
fz_always(ctx)
fz_drop_buffer(ctx, stmbuf);
fz_catch(ctx)
fz_rethrow(ctx);
return dst;
}
/* Load text stream or text string and convert to UTF-8 */
char *
pdf_load_stream_or_string_as_utf8(fz_context *ctx, pdf_obj *src)
{
if (pdf_is_stream(ctx, src))
return pdf_new_utf8_from_pdf_stream_obj(ctx, src);
return pdf_new_utf8_from_pdf_string_obj(ctx, src);
}
static pdf_obj *
pdf_new_text_string_utf16be(fz_context *ctx, const char *s)
{
const char *ss;
int c, i, n, a, b;
unsigned char *p;
pdf_obj *obj;
ss = s;
n = 0;
while (*ss)
{
ss += fz_chartorune(&c, ss);
n += (c >= 0x10000) ? 2 : 1;
}
p = fz_malloc(ctx, n * 2 + 2);
i = 0;
p[i++] = 254;
p[i++] = 255;
while (*s)
{
s += fz_chartorune(&c, s);
if (c >= 0x10000)
{
a = (((c - 0x10000) >> 10) & 0x3ff) + 0xD800;
p[i++] = (a>>8) & 0xff;
p[i++] = (a) & 0xff;
b = (((c - 0x10000)) & 0x3ff) + 0xDC00;
p[i++] = (b>>8) & 0xff;
p[i++] = (b) & 0xff;
}
else
{
p[i++] = (c>>8) & 0xff;
p[i++] = (c) & 0xff;
}
}
fz_try(ctx)
obj = pdf_new_string(ctx, (char*)p, i);
fz_always(ctx)
fz_free(ctx, p);
fz_catch(ctx)
fz_rethrow(ctx);
return obj;
}
/*
* Create a PDF 'text string' by encoding input string as either ASCII or UTF-16BE.
* In theory, we could also use PDFDocEncoding.
*/
pdf_obj *
pdf_new_text_string(fz_context *ctx, const char *s)
{
int i = 0;
while (s[i] != 0)
{
if (((unsigned char)s[i]) >= 128)
return pdf_new_text_string_utf16be(ctx, s);
++i;
}
return pdf_new_string(ctx, s, i);
}
pdf_obj *
pdf_parse_array(fz_context *ctx, pdf_document *doc, fz_stream *file, pdf_lexbuf *buf)
{
pdf_obj *ary = NULL;
pdf_obj *obj = NULL;
int64_t a = 0, b = 0, n = 0;
pdf_token tok;
pdf_obj *op = NULL;
fz_var(obj);
ary = pdf_new_array(ctx, doc, 4);
fz_try(ctx)
{
while (1)
{
tok = pdf_lex(ctx, file, buf);
if (tok != PDF_TOK_INT && tok != PDF_TOK_R)
{
if (n > 0)
pdf_array_push_int(ctx, ary, a);
if (n > 1)
pdf_array_push_int(ctx, ary, b);
n = 0;
}
if (tok == PDF_TOK_INT && n == 2)
{
pdf_array_push_int(ctx, ary, a);
a = b;
n --;
}
switch (tok)
{
case PDF_TOK_EOF:
fz_throw(ctx, FZ_ERROR_SYNTAX, "array not closed before end of file");
case PDF_TOK_CLOSE_ARRAY:
op = ary;
goto end;
case PDF_TOK_INT:
if (n == 0)
a = buf->i;
if (n == 1)
b = buf->i;
n ++;
break;
case PDF_TOK_R:
if (n != 2)
fz_throw(ctx, FZ_ERROR_SYNTAX, "cannot parse indirect reference in array");
pdf_array_push_drop(ctx, ary, pdf_new_indirect(ctx, doc, a, b));
n = 0;
break;
case PDF_TOK_OPEN_ARRAY:
obj = pdf_parse_array(ctx, doc, file, buf);
pdf_array_push_drop(ctx, ary, obj);
break;
case PDF_TOK_OPEN_DICT:
obj = pdf_parse_dict(ctx, doc, file, buf);
pdf_array_push_drop(ctx, ary, obj);
break;
case PDF_TOK_NAME:
pdf_array_push_name(ctx, ary, buf->scratch);
break;
case PDF_TOK_REAL:
pdf_array_push_real(ctx, ary, buf->f);
break;
case PDF_TOK_STRING:
pdf_array_push_string(ctx, ary, buf->scratch, buf->len);
break;
case PDF_TOK_TRUE:
pdf_array_push_bool(ctx, ary, 1);
break;
case PDF_TOK_FALSE:
pdf_array_push_bool(ctx, ary, 0);
break;
case PDF_TOK_NULL:
pdf_array_push(ctx, ary, PDF_NULL);
break;
default:
pdf_array_push(ctx, ary, PDF_NULL);
break;
}
}
end:
{}
}
fz_catch(ctx)
{
pdf_drop_obj(ctx, ary);
fz_rethrow(ctx);
}
return op;
}
pdf_obj *
pdf_parse_dict(fz_context *ctx, pdf_document *doc, fz_stream *file, pdf_lexbuf *buf)
{
pdf_obj *dict;
pdf_obj *key = NULL;
pdf_obj *val = NULL;
pdf_token tok;
int64_t a, b;
dict = pdf_new_dict(ctx, doc, 8);
fz_var(key);
fz_var(val);
fz_try(ctx)
{
while (1)
{
tok = pdf_lex(ctx, file, buf);
skip:
if (tok == PDF_TOK_CLOSE_DICT)
break;
/* for BI .. ID .. EI in content streams */
if (tok == PDF_TOK_KEYWORD && !strcmp(buf->scratch, "ID"))
break;
if (tok != PDF_TOK_NAME)
fz_throw(ctx, FZ_ERROR_SYNTAX, "invalid key in dict");
key = pdf_new_name(ctx, buf->scratch);
tok = pdf_lex(ctx, file, buf);
switch (tok)
{
case PDF_TOK_OPEN_ARRAY:
val = pdf_parse_array(ctx, doc, file, buf);
break;
case PDF_TOK_OPEN_DICT:
val = pdf_parse_dict(ctx, doc, file, buf);
break;
case PDF_TOK_NAME: val = pdf_new_name(ctx, buf->scratch); break;
case PDF_TOK_REAL: val = pdf_new_real(ctx, buf->f); break;
case PDF_TOK_STRING: val = pdf_new_string(ctx, buf->scratch, buf->len); break;
case PDF_TOK_TRUE: val = PDF_TRUE; break;
case PDF_TOK_FALSE: val = PDF_FALSE; break;
case PDF_TOK_NULL: val = PDF_NULL; break;
case PDF_TOK_INT:
/* 64-bit to allow for numbers > INT_MAX and overflow */
a = buf->i;
tok = pdf_lex(ctx, file, buf);
if (tok == PDF_TOK_CLOSE_DICT || tok == PDF_TOK_NAME ||
(tok == PDF_TOK_KEYWORD && !strcmp(buf->scratch, "ID")))
{
val = pdf_new_int(ctx, a);
pdf_dict_put(ctx, dict, key, val);
pdf_drop_obj(ctx, val);
val = NULL;
pdf_drop_obj(ctx, key);
key = NULL;
goto skip;
}
if (tok == PDF_TOK_INT)
{
b = buf->i;
tok = pdf_lex(ctx, file, buf);
if (tok == PDF_TOK_R)
{
val = pdf_new_indirect(ctx, doc, a, b);
break;
}
}
fz_warn(ctx, "invalid indirect reference in dict");
val = PDF_NULL;
break;
default:
val = PDF_NULL;
break;
}
pdf_dict_put(ctx, dict, key, val);
pdf_drop_obj(ctx, val);
val = NULL;
pdf_drop_obj(ctx, key);
key = NULL;
}
}
fz_catch(ctx)
{
pdf_drop_obj(ctx, dict);
pdf_drop_obj(ctx, key);
pdf_drop_obj(ctx, val);
fz_rethrow(ctx);
}
return dict;
}
pdf_obj *
pdf_parse_stm_obj(fz_context *ctx, pdf_document *doc, fz_stream *file, pdf_lexbuf *buf)
{
pdf_token tok;
tok = pdf_lex(ctx, file, buf);
switch (tok)
{
case PDF_TOK_OPEN_ARRAY:
return pdf_parse_array(ctx, doc, file, buf);
case PDF_TOK_OPEN_DICT:
return pdf_parse_dict(ctx, doc, file, buf);
case PDF_TOK_NAME: return pdf_new_name(ctx, buf->scratch);
case PDF_TOK_REAL: return pdf_new_real(ctx, buf->f);
case PDF_TOK_STRING: return pdf_new_string(ctx, buf->scratch, buf->len);
case PDF_TOK_TRUE: return PDF_TRUE;
case PDF_TOK_FALSE: return PDF_FALSE;
case PDF_TOK_NULL: return PDF_NULL;
case PDF_TOK_INT: return pdf_new_int(ctx, buf->i);
default: fz_throw(ctx, FZ_ERROR_SYNTAX, "unknown token in object stream");
}
}
pdf_obj *
pdf_parse_ind_obj(fz_context *ctx, pdf_document *doc,
fz_stream *file, pdf_lexbuf *buf,
int *onum, int *ogen, int64_t *ostmofs, int *try_repair)
{
pdf_obj *obj = NULL;
int num = 0, gen = 0;
int64_t stm_ofs;
pdf_token tok;
int64_t a, b;
int read_next_token = 1;
fz_var(obj);
tok = pdf_lex(ctx, file, buf);
if (tok != PDF_TOK_INT)
{
if (try_repair)
*try_repair = 1;
fz_throw(ctx, FZ_ERROR_SYNTAX, "expected object number");
}
num = buf->i;
if (num < 0 || num > PDF_MAX_OBJECT_NUMBER)
fz_throw(ctx, FZ_ERROR_SYNTAX, "object number out of range");
tok = pdf_lex(ctx, file, buf);
if (tok != PDF_TOK_INT)
{
if (try_repair)
*try_repair = 1;
fz_throw(ctx, FZ_ERROR_SYNTAX, "expected generation number (%d ? obj)", num);
}
gen = buf->i;
tok = pdf_lex(ctx, file, buf);
if (tok != PDF_TOK_OBJ)
{
if (try_repair)
*try_repair = 1;
fz_throw(ctx, FZ_ERROR_SYNTAX, "expected 'obj' keyword (%d %d ?)", num, gen);
}
tok = pdf_lex(ctx, file, buf);
switch (tok)
{
case PDF_TOK_OPEN_ARRAY:
obj = pdf_parse_array(ctx, doc, file, buf);
break;
case PDF_TOK_OPEN_DICT:
obj = pdf_parse_dict(ctx, doc, file, buf);
break;
case PDF_TOK_NAME: obj = pdf_new_name(ctx, buf->scratch); break;
case PDF_TOK_REAL: obj = pdf_new_real(ctx, buf->f); break;
case PDF_TOK_STRING: obj = pdf_new_string(ctx, buf->scratch, buf->len); break;
case PDF_TOK_TRUE: obj = PDF_TRUE; break;
case PDF_TOK_FALSE: obj = PDF_FALSE; break;
case PDF_TOK_NULL: obj = PDF_NULL; break;
case PDF_TOK_INT:
a = buf->i;
tok = pdf_lex(ctx, file, buf);
if (tok == PDF_TOK_STREAM || tok == PDF_TOK_ENDOBJ)
{
obj = pdf_new_int(ctx, a);
read_next_token = 0;
break;
}
else if (tok == PDF_TOK_INT)
{
b = buf->i;
tok = pdf_lex(ctx, file, buf);
if (tok == PDF_TOK_R)
{
obj = pdf_new_indirect(ctx, doc, a, b);
break;
}
}
fz_throw(ctx, FZ_ERROR_SYNTAX, "expected 'R' keyword (%d %d R)", num, gen);
case PDF_TOK_ENDOBJ:
obj = PDF_NULL;
read_next_token = 0;
break;
default:
fz_throw(ctx, FZ_ERROR_SYNTAX, "syntax error in object (%d %d R)", num, gen);
}
fz_try(ctx)
{
if (read_next_token)
tok = pdf_lex(ctx, file, buf);
if (tok == PDF_TOK_STREAM)
{
int c = fz_read_byte(ctx, file);
while (c == ' ')
c = fz_read_byte(ctx, file);
if (c == '\r')
{
c = fz_peek_byte(ctx, file);
if (c != '\n')
fz_warn(ctx, "line feed missing after stream begin marker (%d %d R)", num, gen);
else
fz_read_byte(ctx, file);
}
stm_ofs = fz_tell(ctx, file);
}
else if (tok == PDF_TOK_ENDOBJ)
{
stm_ofs = 0;
}
else
{
fz_warn(ctx, "expected 'endobj' or 'stream' keyword (%d %d R)", num, gen);
stm_ofs = 0;
}
}
fz_catch(ctx)
{
pdf_drop_obj(ctx, obj);
fz_rethrow(ctx);
}
if (onum) *onum = num;
if (ogen) *ogen = gen;
if (ostmofs) *ostmofs = stm_ofs;
return obj;
}