Patch adding support for ibs= and obs= to dd
authorandersen <andersen@69ca8d6d-28ef-0310-b511-8ec308f3f277>
Mon, 5 Apr 2004 14:30:15 +0000 (14:30 +0000)
committerandersen <andersen@69ca8d6d-28ef-0310-b511-8ec308f3f277>
Mon, 5 Apr 2004 14:30:15 +0000 (14:30 +0000)
git-svn-id: svn://busybox.net/trunk/busybox@8688 69ca8d6d-28ef-0310-b511-8ec308f3f277

patches/dd_ibs_and_obs.diff [new file with mode: 0644]

diff --git a/patches/dd_ibs_and_obs.diff b/patches/dd_ibs_and_obs.diff
new file mode 100644 (file)
index 0000000..3bbf4b9
--- /dev/null
@@ -0,0 +1,252 @@
+This patch adds support of ibs= and obs= to dd.
+----
+Hideki IWAMOTO  h-iwamoto@kit.hi-ho.ne.jp
+
+
+--- a/include/usage.h  29 Mar 2004 08:20:08 -0000      1.198
++++ b/include/usage.h  4 Apr 2004 07:15:21 -0000
+@@ -309,13 +309,15 @@
+       "64\n"
+ #define dd_trivial_usage \
+-      "[if=FILE] [of=FILE] [bs=N] [count=N] [skip=N]\n" \
+-      "\t  [seek=N] [conv=notrunc|noerror|sync]"
++      "[if=FILE] [of=FILE] [ibs=N] [obs=N] [bs=N] [count=N]\n" \
++      "\t  [skip=N] [seek=N] [conv=notrunc|noerror|sync]"
+ #define dd_full_usage \
+       "Copy a file, converting and formatting according to options\n\n" \
+       "\tif=FILE\t\tread from FILE instead of stdin\n" \
+       "\tof=FILE\t\twrite to FILE instead of stdout\n" \
+-      "\tbs=N\t\tread and write N bytes at a time\n" \
++      "\tibs=N\t\tread N bytes at a time\n" \
++      "\tobs=N\t\twrite N bytes at a time\n" \
++      "\tbs=N\t\tforce ibs=N and obs=N\n" \
+       "\tcount=N\t\tcopy only N input blocks\n" \
+       "\tskip=N\t\tskip N input blocks\n" \
+       "\tseek=N\t\tskip N output blocks\n" \
+@@ -323,6 +325,8 @@
+       "\tconv=noerror\tcontinue after read errors\n" \
+       "\tconv=sync\tpad blocks with zeros\n" \
+       "\n" \
++      "If the bs= expr operand is not specified, the input is processed and collected\n" \
++      "into full-sized output blocks until the end of the input is reached.\n" \
+       "Numbers may be suffixed by c (x1), w (x2), b (x512), kD (x1000), k (x1024),\n" \
+       "MD (x1000000), M (x1048576), GD (x1000000000) or G (x1073741824)."
+ #define dd_example_usage \
+--- a/coreutils/dd.c   30 Jan 2004 22:24:32 -0000      1.55
++++ b/coreutils/dd.c   4 Apr 2004 07:15:21 -0000
+@@ -30,6 +30,10 @@
+ #include <fcntl.h>
+ #include "busybox.h"
++#define C_NOERROR     0x0001
++#define C_TRUNC               0x0002
++#define C_SYNC                0x0004
++#define C_TWOBUFS     0x0008
+ static const struct suffix_mult dd_suffixes[] = {
+       { "c", 1 },
+@@ -51,13 +55,13 @@
+       size_t in_full = 0;
+       size_t in_part = 0;
+       size_t count = -1;
+-      size_t bs = 512;
++      size_t ibs = 512;
++      size_t obs = 512;
++      size_t oc = 0;
+       ssize_t n;
+       off_t seek = 0;
+       off_t skip = 0;
+-      int sync_flag = FALSE;
+-      int noerror = FALSE;
+-      int trunc_flag = TRUE;
++      unsigned int dd_flags = C_TWOBUFS | C_TRUNC;
+       int oflag;
+       int ifd;
+       int ofd;
+@@ -65,11 +69,18 @@
+       const char *infile = NULL;
+       const char *outfile = NULL;
+       char *buf;
++      char *ibuf;
++      char *obuf;
+       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 (strncmp("ibs=", argv[i], 4) == 0)
++                      ibs = bb_xparse_number(argv[i]+4, dd_suffixes);
++              else if (strncmp("obs=", argv[i], 4) == 0)
++                      obs = bb_xparse_number(argv[i]+4, dd_suffixes);
++              else if (strncmp("bs=", argv[i], 3) == 0) {
++                      ibs = obs = bb_xparse_number(argv[i]+3, dd_suffixes);
++                      dd_flags &= ~C_TWOBUFS;
++              } else if (strncmp("count=", argv[i], 6) == 0)
+                       count = bb_xparse_number(argv[i]+6, dd_suffixes);
+               else if (strncmp("seek=", argv[i], 5) == 0)
+                       seek = bb_xparse_number(argv[i]+5, dd_suffixes);
+@@ -83,13 +94,13 @@
+                       buf = argv[i]+5;
+                       while (1) {
+                               if (strncmp("notrunc", buf, 7) == 0) {
+-                                      trunc_flag = FALSE;
++                                      dd_flags &= ~C_TRUNC;
+                                       buf += 7;
+                               } else if (strncmp("sync", buf, 4) == 0) {
+-                                      sync_flag = TRUE;
++                                      dd_flags |= C_SYNC;
+                                       buf += 4;
+                               } else if (strncmp("noerror", buf, 7) == 0) {
+-                                      noerror = TRUE;
++                                      dd_flags |= C_NOERROR;
+                                       buf += 7;
+                               } else {
+                                       bb_error_msg_and_die("invalid conversion `%s'", argv[i]+5);
+@@ -103,7 +114,12 @@
+                       bb_show_usage();
+       }
+-      buf = xmalloc(bs);
++      ibuf = xmalloc(ibs);
++
++      if (dd_flags & C_TWOBUFS)
++              obuf = xmalloc(obs);
++      else
++              obuf = ibuf;
+       if (infile != NULL) {
+               ifd = bb_xopen(infile, O_RDONLY);
+@@ -115,7 +131,7 @@
+       if (outfile != NULL) {
+               oflag = O_WRONLY | O_CREAT;
+-              if (!seek && trunc_flag) {
++              if (!seek && (dd_flags & C_TRUNC)) {
+                       oflag |= O_TRUNC;
+               }
+@@ -123,8 +139,8 @@
+                       bb_perror_msg_and_die("%s", outfile);
+               }
+-              if (seek && trunc_flag) {
+-                      if (ftruncate(ofd, seek * bs) < 0) {
++              if (seek && (dd_flags & C_TRUNC)) {
++                      if (ftruncate(ofd, seek * obs) < 0) {
+                               struct stat st;
+                               if (fstat (ofd, &st) < 0 || S_ISREG (st.st_mode) ||
+@@ -139,52 +155,88 @@
+       }
+       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);
+               }
+       }
+       while (in_full + in_part != count) {
+-              if (noerror) {
++              if (dd_flags & C_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;
++                      if (dd_flags & C_NOERROR) {
++                              n = ibs;
+                               bb_perror_msg("%s", infile);
+                       } else {
+                               bb_perror_msg_and_die("%s", infile);
+                       }
+               }
+-              if (n == 0) {
+-                      break;
+-              }
+-              if (n == bs) {
++              if (n == ibs) {
+                       in_full++;
+               } else {
+                       in_part++;
++                      if (dd_flags & C_SYNC) {
++                              memset(ibuf + n, '\0', ibs - n);
++                              n = ibs;
++                      }
+               }
+-              if (sync_flag) {
+-                      memset(buf + n, '\0', bs - n);
+-                      n = bs;
++
++              if (dd_flags & C_TWOBUFS) {
++                      size_t d;
++                      char *tmp = ibuf;
++
++                      while (n) {
++                              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 (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 (oc) {
++              if (bb_full_write(ofd, obuf, oc) < 0) {
+                       bb_perror_msg_and_die("%s", outfile);
+               }
+-              if (n == bs) {
+-                      out_full++;
+-              } else {
+-                      out_part++;
+-              }
++              out_part++;
+       }
+       if (close (ifd) < 0) {
+
+