/**
* This routine maps the SAC file header into memory from
* a buffer containing it in disk file format.
* In the disk file (deriving from the FORTRAN version of
* SAC) these strings are essentially concatenated without
* null termination. In memory, they are carried about as
* null terminated strings. This routine picks out the
* strings and null terminates them, storing them in the
* in memory working storage area.
*
* @param memarray
* Output
* @param buffer
* Input
* @param lswap
* Swap the buffer if necessary
*
*/
void
map_hdr_in(float *memarray,
float *buffer,
int lswap) {
char *ptr1, *ptr2;
int idx;
/* First get the header values for the non character
* fields fhdr, nhdr, ihdr and lhdr. These are copied
* straight across.
*/
ptr1 = (char *)memarray;
ptr2 = (char *)buffer;
memcpy(ptr1,ptr2, SAC_HEADER_NUMBERS * sizeof(float));
/* byteswap numeric data if necessary. */
if( lswap ){
for( idx = 0 ; idx < SAC_HEADER_NUMBERS ; idx++, ptr1 += SAC_HEADER_SIZEOF_NUMBER )
byteswap( (void *)ptr1, SAC_HEADER_SIZEOF_NUMBER ) ;
}
/* Now copy the character variables into the memory
* buffer, supplying the additional null termination
* character.
*/
map_chdr_in(memarray + SAC_HEADER_NUMBERS,
buffer + SAC_HEADER_NUMBERS);
return;
}
/*
* read_head_in:
* read sac header in and deal with possible byte swap.
*
* IN:
* const char *name : file name, only for debug
* SACHEAD *hd : header to be filled
* FILE *strm : file handler
*
* Return:
* 0 : Succeed and no byte swap
* 1 : Succeed and byte swap
* -1 : fail.
*/
static int read_head_in(const char *name, SACHEAD *hd, FILE *strm)
{
char *buffer;
int lswap;
if (sizeof(float) != SAC_DATA_SIZEOF || sizeof(int) != SAC_DATA_SIZEOF) {
fprintf(stderr, "Mismatch in size of basic data type!\n");
return -1;
}
/* read numeric parts of the SAC header */
if (fread(hd, SAC_HEADER_NUMBERS_SIZE, 1, strm) != 1) {
fprintf(stderr, "Error in reading SAC header %s\n", name);
return -1;
}
/* Check Header Version and Endian */
lswap = check_sac_nvhdr(hd->nvhdr);
if (lswap == -1) {
fprintf(stderr, "Warning: %s not in sac format.\n", name);
return -1;
} else if (lswap == TRUE) {
byte_swap((char *)hd, SAC_HEADER_NUMBERS_SIZE);
}
/* read string parts of the SAC header */
if ((buffer = (char *)malloc(SAC_HEADER_STRINGS_SIZE)) == NULL) {
fprintf(stderr, "Error in allocating memory %s\n", name);
return -1;
}
if (fread(buffer, SAC_HEADER_STRINGS_SIZE, 1, strm) != 1) {
fprintf(stderr, "Error in reading SAC header %s\n", name);
free(buffer);
return -1;
}
map_chdr_in((char *)(hd)+SAC_HEADER_NUMBERS_SIZE, buffer);
free(buffer);
return lswap;
}
