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PhotoRec: parse PNG/JNG/MNG files

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This commit is contained in:
Christophe Grenier 2010-07-23 08:46:17 +02:00
parent 8d5c9fc438
commit d62dbeee25
1 changed files with 41 additions and 14 deletions
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55
src/file_png.c
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@ -40,7 +40,8 @@ extern const file_hint_t file_hint_doc;
static void register_header_check_png(file_stat_t *file_stat);
static int header_check_png(const unsigned char *buffer, const unsigned int buffer_size, const unsigned int safe_header_only, const file_recovery_t *file_recovery, file_recovery_t *file_recovery_new);
static void file_check_png(file_recovery_t *file_recovery);
static int data_check_png(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery);
static int data_check_mng(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery);
const file_hint_t file_hint_png= {
.extension="png",
@ -68,17 +69,19 @@ static int header_check_png(const unsigned char *buffer, const unsigned int buff
if(memcmp(buffer,jng_header,sizeof(jng_header))==0)
{
reset_file_recovery(file_recovery_new);
file_recovery_new->min_filesize=92;
file_recovery_new->file_check=file_check_png;
file_recovery_new->extension="jng";
file_recovery_new->calculated_file_size=8;
file_recovery_new->data_check=&data_check_png;
file_recovery_new->file_check=&file_check_size;
return 1;
}
if(memcmp(buffer,mng_header,sizeof(mng_header))==0)
{
reset_file_recovery(file_recovery_new);
file_recovery_new->min_filesize=92;
file_recovery_new->file_check=file_check_png;
file_recovery_new->extension="mng";
file_recovery_new->calculated_file_size=8;
file_recovery_new->data_check=&data_check_mng;
file_recovery_new->file_check=&file_check_size;
return 1;
}
/* SolidWorks files contains a png */
@ -90,20 +93,44 @@ static int header_check_png(const unsigned char *buffer, const unsigned int buff
if(memcmp(buffer,png_header,sizeof(png_header))==0)
{
reset_file_recovery(file_recovery_new);
file_recovery_new->min_filesize=92;
file_recovery_new->file_check=file_check_png;
file_recovery_new->extension=file_hint_png.extension;
file_recovery_new->calculated_file_size=8;
file_recovery_new->data_check=&data_check_png;
file_recovery_new->file_check=&file_check_size;
return 1;
}
return 0;
}
static void file_check_png(file_recovery_t *file_recovery)
static int data_check_mng(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery)
{
const unsigned char mng_footer[4]= {'M','E','N','D'};
const unsigned char png_footer[4]= {'I','E','N','D'};
if(strstr(file_recovery->filename,".mng")!=NULL)
file_search_footer(file_recovery, mng_footer, sizeof(mng_footer), 4);
else
file_search_footer(file_recovery, png_footer, sizeof(png_footer), 4);
static const unsigned char mng_footer[4]= {'M','E','N','D'};
while(file_recovery->calculated_file_size + buffer_size/2 >= file_recovery->file_size &&
file_recovery->calculated_file_size + 8 < file_recovery->file_size + buffer_size/2)
{
unsigned int i=file_recovery->calculated_file_size - file_recovery->file_size + buffer_size/2;
/* chunk: length, type, data, crc */
file_recovery->calculated_file_size+=(buffer[i]<<24)+(buffer[i+1]<<16)+(buffer[i+2]<<8)+buffer[i+3];
file_recovery->calculated_file_size+=12;
if(memcmp(&buffer[i+4], mng_footer, sizeof(mng_footer))==0)
return 2;
}
return 1;
}
static int data_check_png(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery)
{
static const unsigned char png_footer[4]= {'I','E','N','D'};
while(file_recovery->calculated_file_size + buffer_size/2 >= file_recovery->file_size &&
file_recovery->calculated_file_size + 8 < file_recovery->file_size + buffer_size/2)
{
unsigned int i=file_recovery->calculated_file_size - file_recovery->file_size + buffer_size/2;
/* chunk: length, type, data, crc */
file_recovery->calculated_file_size+=(buffer[i]<<24)+(buffer[i+1]<<16)+(buffer[i+2]<<8)+buffer[i+3];
file_recovery->calculated_file_size+=12;
if(memcmp(&buffer[i+4], png_footer, sizeof(png_footer))==0)
return 2;
}
return 1;
}