use bb_xbind/bb_xlisten
[oweals/busybox.git] / coreutils / dd.c
index 9468cddfc6a81f0900d554f2810a6a0a3856351d..53aa085ed79f041bfc5d2e445ad72fd7282eb34b 100644 (file)
+/* vi: set sw=4 ts=4: */
 /*
  * Mini dd implementation for busybox
  *
- * Copyright (C) 1999 by Lineo, inc.
- * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
- * based in part on code taken from sash. 
  *
- * Copyright (c) 1999 by David I. Bell
- * Permission is granted to use, distribute, or modify this source,
- * provided that this copyright notice remains intact.
- *
- * Permission to distribute this code under the GPL has been granted.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Copyright (C) 2000,2001  Matt Kraai
  *
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  */
 
-
-#include "internal.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <stdlib.h>
 #include <stdio.h>
+#include <unistd.h>
+#include <string.h>
 #include <fcntl.h>
-#include <errno.h>
-
-static const char dd_usage[] =
-"dd [if=name] [of=name] [bs=n] [count=n]\n\n"
-"Copy a file, converting and formatting according to options\n\n"
-"\tif=FILE\tread from FILE instead of stdin\n"
-"\tof=FILE\twrite to FILE instead of stout\n"
-"\tbs=n\tread and write N BYTES at a time\n"
-"\tcount=n\tcopy only n input blocks\n"
-//"\tskip=n\tskip n input blocks\n"
-"\n"
-"BYTES may be suffixed: by k for x1024, b for x512, and w for x2.\n";
-
-
-
-
-/*
- * Read a number with a possible multiplier.
- * Returns -1 if the number format is illegal.
- */
-static long getNum (const char *cp)
+#include <signal.h>  // For FEATURE_DD_SIGNAL_HANDLING
+#include "busybox.h"
+
+static const struct suffix_mult dd_suffixes[] = {
+       { "c", 1 },
+       { "w", 2 },
+       { "b", 512 },
+       { "kD", 1000 },
+       { "k", 1024 },
+       { "MD", 1000000 },
+       { "M", 1048576 },
+       { "GD", 1000000000 },
+       { "G", 1073741824 },
+       { NULL, 0 }
+};
+
+static size_t out_full;
+static size_t out_part;
+static size_t in_full;
+static size_t in_part;
+
+static void dd_output_status(int cur_signal)
 {
-    long value;
-
-    if (!isDecimal (*cp))
-       return -1;
-
-    value = 0;
-
-    while (isDecimal (*cp))
-       value = value * 10 + *cp++ - '0';
+       fprintf(stderr, "%ld+%ld records in\n%ld+%ld records out\n",
+                       (long)in_full, (long)in_part,
+                       (long)out_full, (long)out_part);
+}
 
-    switch (*cp++) {
-    case 'k':
-       value *= 1024;
-       break;
+int dd_main(int argc, char **argv)
+{
+       size_t count = -1, oc = 0, ibs = 512, obs = 512;
+       ssize_t n;
+       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)
+       {
+               struct sigaction sa;
+
+               memset(&sa, 0, sizeof(sa));
+               sa.sa_handler = dd_output_status; 
+               sa.sa_flags = SA_RESTART;
+               sigemptyset(&sa.sa_mask);
+               sigaction(SIGUSR1, &sa, 0); 
+       }
 
-    case 'b':
-       value *= 512;
-       break;
+       for (i = 1; i < argc; i++) {
+               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))
+                       seek = bb_xparse_number(argv[i]+5, dd_suffixes);
+               else if (!strncmp("skip=", argv[i], 5))
+                       skip = bb_xparse_number(argv[i]+5, dd_suffixes);
+               else if (!strncmp("if=", argv[i], 3))
+                       infile = argv[i]+3;
+               else if (!strncmp("of=", argv[i], 3))
+                       outfile = argv[i]+3;
+               else if (ENABLE_FEATURE_DD_IBS_OBS && !strncmp("conv=", argv[i], 5)) {
+                       ibuf = argv[i]+5;
+                       while (1) {
+                               if (!strncmp("notrunc", ibuf, 7)) {
+                                       trunc_flag = FALSE;
+                                       ibuf += 7;
+                               } else if (!strncmp("sync", ibuf, 4)) {
+                                       sync_flag = TRUE;
+                                       ibuf += 4;
+                               } else if (!strncmp("noerror", ibuf, 7)) {
+                                       noerror = TRUE;
+                                       ibuf += 7;
+                               } else {
+                                       bb_error_msg_and_die("invalid conversion `%s'", argv[i]+5);
+                               }
+                               if (ibuf[0] == '\0') break;
+                               if (ibuf[0] == ',') ibuf++;
+                       }
+               } else
+                       bb_show_usage();
+       }
+       ibuf = xmalloc(ibs);
 
-    case 'w':
-       value *= 2;
-       break;
+       if (twobufs_flag) obuf = xmalloc(obs);
+       else obuf = ibuf;
 
-    case '\0':
-       return value;
+       if (infile != NULL) {
+               ifd = bb_xopen(infile, O_RDONLY);
+       } else {
+               ifd = STDIN_FILENO;
+               infile = bb_msg_standard_input;
+       }
 
-    default:
-       return -1;
-    }
+       if (outfile != NULL) {
+               oflag = O_WRONLY | O_CREAT;
 
-    if (*cp)
-       return -1;
+               if (!seek && trunc_flag) {
+                       oflag |= O_TRUNC;
+               }
 
-    return value;
-}
+               ofd = bb_xopen3(outfile, oflag, 0666);
 
+               if (seek && trunc_flag) {
+                       if (ftruncate(ofd, seek * obs) < 0) {
+                               struct stat st;
 
-extern int dd_main (int argc, char **argv)
-{
-    const char *inFile;
-    const char *outFile;
-    char *cp;
-    int inFd;
-    int outFd;
-    int inCc = 0;
-    int outCc;
-    int skipBlocks;
-    int blockSize;
-    long count;
-    long intotal;
-    long outTotal;
-    unsigned char *buf;
-
-    inFile = NULL;
-    outFile = NULL;
-    blockSize = 512;
-    skipBlocks = 0;
-    count = 1;
-
-
-    argc--;
-    argv++;
-
-    /* Parse any options */
-    while (argc) {
-       if (inFile == NULL && (strncmp(*argv, "if", 2) == 0))
-           inFile=((strchr(*argv, '='))+1);
-       else if (outFile == NULL && (strncmp(*argv, "of", 2) == 0))
-           outFile=((strchr(*argv, '='))+1);
-       else if (strncmp("count", *argv, 5) == 0) {
-           count = getNum ((strchr(*argv, '='))+1);
-           if (count <= 0) {
-               fprintf (stderr, "Bad count value %ld\n", count);
-               goto usage;
-           }
+                               if (fstat (ofd, &st) < 0 || S_ISREG (st.st_mode) ||
+                                               S_ISDIR (st.st_mode)) {
+                                       bb_perror_msg_and_die("%s", outfile);
+                               }
+                       }
+               }
+       } else {
+               ofd = STDOUT_FILENO;
+               outfile = bb_msg_standard_output;
        }
-       else if (strncmp(*argv, "bs", 2) == 0) {
-           blockSize = getNum ((strchr(*argv, '='))+1);
-           if (blockSize <= 0) {
-               fprintf (stderr, "Bad block size value %d\n", blockSize);
-               goto usage;
-           }
+
+       if (skip) {
+               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 0
-       else if (strncmp(*argv, "skip", 4) == 0) {
-           skipBlocks = atoi( *argv); 
-           if (skipBlocks <= 0) {
-               fprintf (stderr, "Bad skip value %d\n", skipBlocks);
-               goto usage;
-           }
 
+       if (seek) {
+               if (lseek(ofd, seek * obs, SEEK_CUR) < 0) {
+                       bb_perror_msg_and_die("%s", outfile);
+               }
        }
-#endif
-       else {
-           goto usage;
+
+       while (in_full + in_part != count) {
+               if (noerror) {
+                       /* Pre-zero the buffer when doing the noerror thing */
+                       memset(ibuf, '\0', ibs);
+               }
+
+               n = safe_read(ifd, ibuf, ibs);
+               if (n == 0) {
+                       break;
+               }
+               if (n < 0) {
+                       if (noerror) {
+                               n = ibs;
+                               bb_perror_msg("%s", infile);
+                       } else {
+                               bb_perror_msg_and_die("%s", infile);
+                       }
+               }
+               if ((size_t)n == ibs) {
+                       in_full++;
+               } else {
+                       in_part++;
+                       if (sync_flag) {
+                               memset(ibuf + n, '\0', ibs - n);
+                               n = ibs;
+                       }
+               }
+               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++;
+               }
        }
-       argc--;
-       argv++;
-    }
-
-    buf = malloc (blockSize);
-    if (buf == NULL) {
-       fprintf (stderr, "Cannot allocate buffer\n");
-       exit( FALSE);
-    }
-
-    intotal = 0;
-    outTotal = 0;
-
-    if (inFile == NULL)
-       inFd = STDIN;
-    else
-       inFd = open (inFile, 0);
-
-    if (inFd < 0) {
-       perror (inFile);
-       free (buf);
-       exit( FALSE);
-    }
-
-    if (outFile == NULL)
-       outFd = STDOUT;
-    else
-       outFd = creat (outFile, 0666);
-
-    if (outFd < 0) {
-       perror (outFile);
-       close (inFd);
-       free (buf);
-       exit( FALSE);
-    }
-
-    //lseek(inFd, skipBlocks*blockSize, SEEK_SET);
-    while (outTotal < count * blockSize) {
-       inCc = read (inFd, buf, blockSize);
-       if (inCc < 0) {
-           perror (inFile);
-           goto cleanup;
+       
+       if (ENABLE_FEATURE_DD_IBS_OBS && oc) {
+               if (bb_full_write(ofd, obuf, oc) < 0) {
+                       bb_perror_msg_and_die("%s", outfile);
+               }
+               out_part++;
        }
-       intotal += inCc;
-       cp = buf;
-
-       while (intotal > outTotal) {
-           if (outTotal + inCc > count * blockSize)
-               inCc = count * blockSize - outTotal;
-           outCc = write (outFd, cp, inCc);
-           if (outCc < 0) {
-               perror (outFile);
-               goto cleanup;
-           }
-
-           inCc -= outCc;
-           cp += outCc;
-           outTotal += outCc;
+       if (close (ifd) < 0) {
+               bb_perror_msg_and_die("%s", infile);
        }
-    }
-
-    if (inCc < 0)
-       perror (inFile);
 
-  cleanup:
-    close (inFd);
-    close (outFd);
-    free (buf);
+       if (close (ofd) < 0) {
+               bb_perror_msg_and_die("%s", outfile);
+       }
 
-    printf ("%ld+%d records in\n", intotal / blockSize,
-           (intotal % blockSize) != 0);
-    printf ("%ld+%d records out\n", outTotal / blockSize,
-           (outTotal % blockSize) != 0);
-    exit( TRUE);
-  usage:
+       dd_output_status(0);
 
-    usage( dd_usage);
+       return EXIT_SUCCESS;
 }
-
-