diff options
Diffstat (limited to 'coreutils/dd.c')
| -rw-r--r-- | coreutils/dd.c | 139 |
1 files changed, 83 insertions, 56 deletions
diff --git a/coreutils/dd.c b/coreutils/dd.c index 378e212..53aa085 100644 --- a/coreutils/dd.c +++ b/coreutils/dd.c @@ -45,21 +45,13 @@ static void dd_output_status(int cur_signal) int dd_main(int argc, char **argv) { - size_t count = -1; - size_t bs = 512; + size_t count = -1, oc = 0, ibs = 512, obs = 512; ssize_t n; - off_t seek = 0; - off_t skip = 0; - int sync_flag = FALSE; - int noerror = FALSE; - int trunc_flag = TRUE; - int oflag; - int ifd; - int ofd; - int i; - const char *infile = NULL; - const char *outfile = NULL; - char *buf; + off_t seek = 0, skip = 0; + int sync_flag = FALSE, noerror = FALSE, trunc_flag = TRUE, twobufs_flag = 0, + oflag, ifd, ofd, i; + const char *infile = NULL, *outfile = NULL; + char *ibuf, *obuf; if (ENABLE_FEATURE_DD_SIGNAL_HANDLING) { @@ -73,43 +65,49 @@ int dd_main(int argc, char **argv) } for (i = 1; i < argc; i++) { - if (strncmp("bs=", argv[i], 3) == 0) - bs = bb_xparse_number(argv[i]+3, dd_suffixes); - else if (strncmp("count=", argv[i], 6) == 0) + if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("ibs=", argv[i], 4)) { + ibs = bb_xparse_number(argv[i]+4, dd_suffixes); + twobufs_flag++; + } else if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("obs=", argv[i], 4)) { + obs = bb_xparse_number(argv[i]+4, dd_suffixes); + twobufs_flag++; + } else if (!strncmp("bs=", argv[i], 3)) { + ibs = obs = bb_xparse_number(argv[i]+3, dd_suffixes); + } else if (!strncmp("count=", argv[i], 6)) count = bb_xparse_number(argv[i]+6, dd_suffixes); - else if (strncmp("seek=", argv[i], 5) == 0) + else if (!strncmp("seek=", argv[i], 5)) seek = bb_xparse_number(argv[i]+5, dd_suffixes); - else if (strncmp("skip=", argv[i], 5) == 0) + else if (!strncmp("skip=", argv[i], 5)) skip = bb_xparse_number(argv[i]+5, dd_suffixes); - else if (strncmp("if=", argv[i], 3) == 0) + else if (!strncmp("if=", argv[i], 3)) infile = argv[i]+3; - else if (strncmp("of=", argv[i], 3) == 0) + else if (!strncmp("of=", argv[i], 3)) outfile = argv[i]+3; - else if (strncmp("conv=", argv[i], 5) == 0) { - buf = argv[i]+5; + else if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("conv=", argv[i], 5)) { + ibuf = argv[i]+5; while (1) { - if (strncmp("notrunc", buf, 7) == 0) { + if (!strncmp("notrunc", ibuf, 7)) { trunc_flag = FALSE; - buf += 7; - } else if (strncmp("sync", buf, 4) == 0) { + ibuf += 7; + } else if (!strncmp("sync", ibuf, 4)) { sync_flag = TRUE; - buf += 4; - } else if (strncmp("noerror", buf, 7) == 0) { + ibuf += 4; + } else if (!strncmp("noerror", ibuf, 7)) { noerror = TRUE; - buf += 7; + ibuf += 7; } else { bb_error_msg_and_die("invalid conversion `%s'", argv[i]+5); } - if (buf[0] == '\0') - break; - if (buf[0] == ',') - buf++; + if (ibuf[0] == '\0') break; + if (ibuf[0] == ',') ibuf++; } } else bb_show_usage(); } + ibuf = xmalloc(ibs); - buf = xmalloc(bs); + if (twobufs_flag) obuf = xmalloc(obs); + else obuf = ibuf; if (infile != NULL) { ifd = bb_xopen(infile, O_RDONLY); @@ -128,7 +126,7 @@ int dd_main(int argc, char **argv) ofd = bb_xopen3(outfile, oflag, 0666); if (seek && trunc_flag) { - if (ftruncate(ofd, seek * bs) < 0) { + if (ftruncate(ofd, seek * obs) < 0) { struct stat st; if (fstat (ofd, &st) < 0 || S_ISREG (st.st_mode) || @@ -143,13 +141,19 @@ int dd_main(int argc, char **argv) } if (skip) { - if (lseek(ifd, skip * bs, SEEK_CUR) < 0) { - bb_perror_msg_and_die("%s", infile); + if (lseek(ifd, skip * ibs, SEEK_CUR) < 0) { + while (skip-- > 0) { + n = safe_read(ifd, ibuf, ibs); + if (n < 0) + bb_perror_msg_and_die("%s", infile); + if (n == 0) + break; + } } } if (seek) { - if (lseek(ofd, seek * bs, SEEK_CUR) < 0) { + if (lseek(ofd, seek * obs, SEEK_CUR) < 0) { bb_perror_msg_and_die("%s", outfile); } } @@ -157,40 +161,63 @@ int dd_main(int argc, char **argv) while (in_full + in_part != count) { if (noerror) { /* Pre-zero the buffer when doing the noerror thing */ - memset(buf, '\0', bs); + memset(ibuf, '\0', ibs); + } + + n = safe_read(ifd, ibuf, ibs); + if (n == 0) { + break; } - n = safe_read(ifd, buf, bs); if (n < 0) { if (noerror) { - n = bs; + n = ibs; bb_perror_msg("%s", infile); } else { bb_perror_msg_and_die("%s", infile); } } - if (n == 0) { - break; - } - if ((size_t)n == bs) { + if ((size_t)n == ibs) { in_full++; } else { in_part++; + if (sync_flag) { + memset(ibuf + n, '\0', ibs - n); + n = ibs; + } } - if (sync_flag) { - memset(buf + n, '\0', bs - n); - n = bs; + if (twobufs_flag) { + char *tmp = ibuf; + while (n) { + size_t d = obs - oc; + + if (d > n) d = n; + memcpy(obuf + oc, tmp, d); + n -= d; + tmp += d; + oc += d; + if (oc == obs) { + if (bb_full_write(ofd, obuf, obs) < 0) { + bb_perror_msg_and_die("%s", outfile); + } + out_full++; + oc = 0; + } + } + } else { + if ((n = bb_full_write(ofd, ibuf, n)) < 0) { + bb_perror_msg_and_die("%s", outfile); + } + if (n == ibs) out_full++; + else out_part++; } - n = bb_full_write(ofd, buf, n); - if (n < 0) { + } + + if (ENABLE_FEATURE_DD_IBS_OBS && oc) { + if (bb_full_write(ofd, obuf, oc) < 0) { bb_perror_msg_and_die("%s", outfile); } - if ((size_t)n == bs) { - out_full++; - } else { - out_part++; - } + out_part++; } - if (close (ifd) < 0) { bb_perror_msg_and_die("%s", infile); } |