diff options
Diffstat (limited to 'osdep/fseeko.c')
-rw-r--r-- | osdep/fseeko.c | 84 |
1 files changed, 84 insertions, 0 deletions
diff --git a/osdep/fseeko.c b/osdep/fseeko.c new file mode 100644 index 0000000000..14f601575a --- /dev/null +++ b/osdep/fseeko.c @@ -0,0 +1,84 @@ +/* + * fseeko.c + * 64-bit versions of fseeko/ftello() for systems which do not have them + */ + +#include "../config.h" + +#if !defined(HAVE_FSEEKO) || !defined(HAVE_FTELLO) +#include <stdio.h> +#include <sys/types.h> +#include <sys/stat.h> +#include <errno.h> +#endif + +#ifdef WIN32 +#define flockfile +#define funlockfile +#endif + +/* + * On BSD/OS and NetBSD (and perhaps others), off_t and fpos_t are the + * same. Standards say off_t is an arithmetic type, but not necessarily + * integral, while fpos_t might be neither. + * + * This is thread-safe on BSD/OS using flockfile/funlockfile. + */ + +#ifndef HAVE_FSEEKO +int +fseeko(FILE *stream, off_t offset, int whence) +{ + off_t floc; + struct stat filestat; + + switch (whence) + { + case SEEK_CUR: + flockfile(stream); + if (fgetpos(stream, &floc) != 0) + goto failure; + floc += offset; + if (fsetpos(stream, &floc) != 0) + goto failure; + funlockfile(stream); + return 0; + break; + case SEEK_SET: + if (fsetpos(stream, &offset) != 0) + return -1; + return 0; + break; + case SEEK_END: + flockfile(stream); + if (fstat(fileno(stream), &filestat) != 0) + goto failure; + floc = filestat.st_size; + if (fsetpos(stream, &floc) != 0) + goto failure; + funlockfile(stream); + return 0; + break; + default: + errno = EINVAL; + return -1; + } + +failure: + funlockfile(stream); + return -1; +} +#endif + + +#ifndef HAVE_FTELLO +off_t +ftello(FILE *stream) +{ + off_t floc; + + if (fgetpos(stream, &floc) != 0) + return -1; + return floc; +} +#endif |