X-Git-Url: http://git.scottworley.com/overonion/blobdiff_plain/9571ed09bf5c97e104eae36ed323c2cd2d4c09b7..639fe3c8c22cf307547d945a833f6999d4dd819e:/reverse.c diff --git a/reverse.c b/reverse.c index ac55a10..02a349f 100644 --- a/reverse.c +++ b/reverse.c @@ -1,70 +1,17 @@ -#define _FILE_OFFSET_BITS 64 +#include "reverse_lib.h" -#define BUFFER_SIZE 4096 - -#include -#include -#include -#include -#include #include +#include +#include #include -void write_all(int fd, const void *buf, size_t count) { - const char* cbuf = buf; - size_t written = 0; - while (written < count) { - int ret = write(fd, &cbuf[written], count - written); - if (ret == -1) { - err(EX_IOERR, "Could not write"); - } - written += ret; - } -} - - int main(int argc, char** argv) { - if (argc != 2) { + if (argc == 1 || (argc == 2 && strcmp(argv[1], "-") == 0)) { + reverse_stream(stdin, stdout); + } else if (argc == 2) { + reverse_file(argv[1], stdout); + } else { errx(EX_USAGE, "Usage: reverse filename"); } - - int fd = open(argv[1], O_RDONLY); - if (fd == -1) { - err(EX_NOINPUT, "Could not open specified file"); - } - - struct stat stats; - if (fstat(fd, &stats) == -1) { - err(EX_NOINPUT, "Could not stat input"); - } - - long page_size = sysconf(_SC_PAGE_SIZE); - off_t pages = (stats.st_size - 1) / page_size + 1; - long map_size = pages * page_size; - char *m = mmap(NULL, map_size, PROT_READ, MAP_SHARED, fd, 0); - if (m == MAP_FAILED) { - err(EX_NOINPUT, "Could not mmap input"); - } - - char buf[BUFFER_SIZE]; - off_t buf_offset = 0; - for (off_t p = stats.st_size - 1; p >= 0; p--) { - buf[buf_offset++] = m[p]; - if (buf_offset >= BUFFER_SIZE) { - write_all(1, buf, buf_offset); - buf_offset = 0; - } - } - if (buf_offset) { - write_all(1, buf, buf_offset); - } - - if (munmap(m, map_size) == -1) { - err(EX_IOERR, "Could not unmap input"); - } - if (close(fd) == -1) { - err(EX_IOERR, "Could not close input"); - } - return 0; }