/* File: file_fits.c Copyright (C) 2008 Christophe GRENIER This software is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #if !defined(SINGLE_FORMAT) || defined(SINGLE_FORMAT_fits) #ifdef HAVE_CONFIG_H #include #endif #ifdef HAVE_STRING_H #include #endif #ifdef HAVE_TIME_H #include #endif #include #include "types.h" #include "filegen.h" #ifdef DEBUG_FITS #include "log.h" #endif /*@ requires valid_register_header_check(file_stat); */ static void register_header_check_fits(file_stat_t *file_stat); const file_hint_t file_hint_fits= { .extension="fits", .description="Flexible Image Transport System", .max_filesize=PHOTOREC_MAX_FILE_SIZE, .recover=1, .enable_by_default=1, .register_header_check=®ister_header_check_fits }; /* FITS is the standard data format used in astronomy, it's also used in quantic physics * Image metadata is store in an ASCII header * Specification can be found at http://fits.gsfc.nasa.gov/ */ /*@ @ requires \valid_read(str + (0 .. 80-1)); @ terminates \true; @ assigns \nothing; @*/ static uint64_t fits_get_val(const unsigned char *str) { unsigned int i; uint64_t val=0; /*@ @ loop assigns i; @ loop variant 80 - i; @*/ for(i=0;i<80 && str[i]!='=';i++); i++; /*@ @ loop assigns i; @ loop variant 80 - i; @*/ for(;i<80 && str[i]==' ';i++); if(i<80 && str[i]=='-') i++; /*@ @ loop invariant val < PHOTOREC_MAX_FILE_SIZE; @ loop assigns i,val; @ loop variant 80 - i; @*/ for(;i<80 && str[i]>='0' && str[i]<='9';i++) { val=val*10+(str[i]-'0'); if(val >= PHOTOREC_MAX_FILE_SIZE) return val; } return val; } /*@ @ requires buffer_size > 0; @ requires \valid_read(buffer + (0 .. buffer_size-1)); @ requires \valid(file_recovery); @ requires \valid(i_pointer); @ requires \separated(buffer+(..), file_recovery, i_pointer); @ requires *i_pointer < buffer_size; @ assigns *i_pointer, file_recovery->time; @ ensures \old(*i_pointer) == *i_pointer || (\old(*i_pointer) <= *i_pointer < buffer_size + 80); @*/ static uint64_t fits_info(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery, unsigned int *i_pointer) { uint64_t naxis_size=1; unsigned int i=*i_pointer; if( i+80 >= buffer_size) return 1; /*@ assert *i_pointer == i; */ /* Header is composed of 80 character fixed-length strings */ /*@ @ loop invariant *i_pointer <= i; @ loop invariant i < buffer_size + 80; @ loop assigns i, naxis_size, file_recovery->time; @ loop variant buffer_size + 80 - i; @*/ for(; i+80 < buffer_size && memcmp(&buffer[i], "END ", 4)!=0; i+=80) { if(naxis_size > PHOTOREC_MAX_FILE_SIZE) naxis_size=0; /*@ assert naxis_size <= PHOTOREC_MAX_FILE_SIZE; */ if(memcmp(&buffer[i], "BITPIX",6)==0) { const uint64_t tmp=fits_get_val(&buffer[i]); if(tmp > PHOTOREC_MAX_FILE_SIZE) naxis_size=0; else if(tmp>0) { /* FIXME overflow */ naxis_size*=(tmp+8-1)/8; } } else if(memcmp(&buffer[i], "NAXIS ",6)==0) { /* NAXIS - range [0:999] */ if(fits_get_val(&buffer[i])==0) naxis_size=0; } else if(memcmp(&buffer[i], "NAXIS",5)==0) { /* NAXISn */ const uint64_t naxis_val=fits_get_val(&buffer[i]); if(naxis_val > PHOTOREC_MAX_FILE_SIZE) naxis_size=0; else { /* FIXME overflow */ naxis_size*=naxis_val; } } else if(memcmp(&buffer[i], "CREA_DAT=", 9)==0) { /* CREA_DAT= '2007-08-29T16:22:09' */ /* 0123456789012345678 */ unsigned int j; /*@ @ loop assigns j; @ loop variant 80 - j; @*/ for(j=0;j<80 && buffer[i+j]!='\'';j++); if(j<60 && buffer[i+j]=='\'') { file_recovery->time=get_time_from_YYYY_MM_DD_HH_MM_SS(&buffer[i+j+1]); } } } /*@ assert *i_pointer <= i < buffer_size + 80; */ *i_pointer=i; return naxis_size; } /*@ @ requires file_recovery->data_check==&data_check_fits; @ requires valid_data_check_param(buffer, buffer_size, file_recovery); @ ensures valid_data_check_result(\result, file_recovery); @ assigns file_recovery->calculated_file_size, file_recovery->time; @*/ static data_check_t data_check_fits(const unsigned char *buffer, const unsigned int buffer_size, file_recovery_t *file_recovery) { /*@ assert file_recovery->calculated_file_size <= PHOTOREC_MAX_FILE_SIZE; */ /*@ assert file_recovery->file_size <= PHOTOREC_MAX_FILE_SIZE; */ /*@ @ loop assigns file_recovery->calculated_file_size, file_recovery->time; @ loop variant file_recovery->file_size + buffer_size/2 - (file_recovery->calculated_file_size + 8); @*/ 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) { const unsigned int i=file_recovery->calculated_file_size + buffer_size/2 - file_recovery->file_size; /*@ assert 0 <= i < buffer_size - 8; */ /*@ assert \valid_read(&buffer[i] + (0 .. 8-1)); */ if(memcmp(&buffer[i], "XTENSION", 8)!=0) break; { unsigned int new_i=i; /*@ assert i==new_i; */ const uint64_t tmp=fits_info(buffer, buffer_size, file_recovery, &new_i); /*@ assert (i==new_i && i < buffer_size - 8) || (i <= new_i < buffer_size + 80); */ /*@ assert i<=new_i; */ const unsigned int diff=new_i-i; #ifdef DEBUG_FITS log_info("data_check_fits cfr=%llu fs=%llu i=%u buffer_size=%u\n", (long long unsigned)file_recovery->calculated_file_size, (long long unsigned)file_recovery->file_size, new_i, buffer_size); #endif if(tmp==0) { file_recovery->data_check=NULL; file_recovery->file_check=NULL; return DC_CONTINUE; } /*@ assert diff < buffer_size + 80; */ file_recovery->calculated_file_size+=(uint64_t)(diff+2880-1)/2880*2880+(tmp+2880-1)/2880*2880; } } if(file_recovery->file_size + buffer_size/2 >= file_recovery->calculated_file_size) return DC_STOP; return DC_CONTINUE; } /*@ @ requires buffer_size >= 10; @ requires separation: \separated(&file_hint_fits, buffer+(..), file_recovery, file_recovery_new); @ requires valid_header_check_param(buffer, buffer_size, safe_header_only, file_recovery, file_recovery_new); @ ensures valid_header_check_result(\result, file_recovery_new); @ assigns *file_recovery_new; @*/ static int header_check_fits(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) { unsigned int i=0; uint64_t naxis_size_max=0; if(file_recovery_new->blocksize >= 80) naxis_size_max=fits_info(buffer, buffer_size, file_recovery_new, &i); if(naxis_size_max > PHOTOREC_MAX_FILE_SIZE) return 0; if(naxis_size_max !=0 && naxis_size_max < 2880) return 0; reset_file_recovery(file_recovery_new); #ifdef DJGPP file_recovery_new->extension="fts"; #else file_recovery_new->extension=file_hint_fits.extension; #endif file_recovery_new->min_filesize=2880; if(naxis_size_max==0) return 1; /* File is composed of several 2880-bytes blocks */ file_recovery_new->data_check=&data_check_fits; file_recovery_new->file_check=&file_check_size; file_recovery_new->calculated_file_size=(i+2880-1)/2880*2880+(naxis_size_max+2880-1)/2880*2880; /*@ assert valid_file_recovery(file_recovery_new); */ return 1; } static void register_header_check_fits(file_stat_t *file_stat) { register_header_check(0, "SIMPLE =", 9, &header_check_fits, file_stat); } #endif