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-rw-r--r--dd.c307
1 files changed, 307 insertions, 0 deletions
diff --git a/dd.c b/dd.c
new file mode 100644
index 000000000..8f1b9d409
--- /dev/null
+++ b/dd.c
@@ -0,0 +1,307 @@
+/*
+ * Copyright (c) 1999 by David I. Bell
+ * Permission is granted to use, distribute, or modify this source,
+ * provided that this copyright notice remains intact.
+ *
+ * The "dd" command, originally taken from sash.
+ *
+ * Permission to distribute this code under the GPL has been granted.
+ * Majorly modified, and bugs fixed for busybox by Erik Andersen <andersee@debian.org> <andersen@lineo.com>
+ */
+
+#include "internal.h"
+#ifdef BB_DD
+
+const char dd_usage[] =
+"Copy a file, converting and formatting according to options\n\
+\n\
+usage: [if=name] [of=name] [bs=n] [count=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\
+\n\
+BYTES may be suffixed: by k for x1024, b for x512, and w for x2.\n";
+
+
+#include <stdio.h>
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <time.h>
+
+
+#define PAR_NONE 0
+#define PAR_IF 1
+#define PAR_OF 2
+#define PAR_BS 3
+#define PAR_COUNT 4
+
+
+typedef struct
+{
+ const char * name;
+ int value;
+} PARAM;
+
+
+static const PARAM params[] =
+{
+ {"if", PAR_IF},
+ {"of", PAR_OF},
+ {"bs", PAR_BS},
+ {"count", PAR_COUNT},
+ {NULL, PAR_NONE}
+};
+
+
+static long getNum(const char * cp);
+
+extern int
+dd_main (struct FileInfo *unused, int argc, char **argv)
+{
+ const char * str;
+ const PARAM * par;
+ const char * inFile;
+ const char * outFile;
+ char * cp;
+ int inFd;
+ int outFd;
+ int inCc=0;
+ int outCc;
+ int blockSize;
+ long count;
+ long intotal;
+ long outTotal;
+ unsigned char* buf;
+ unsigned char localBuf[BUF_SIZE];
+
+ inFile = NULL;
+ outFile = NULL;
+ blockSize = 512;
+ count = 1;
+
+
+ while (--argc > 0)
+ {
+ str = *++argv;
+ cp = strchr(str, '=');
+
+ if (cp == NULL)
+ {
+ fprintf(stderr, "Bad dd argument\n");
+ goto usage;
+ }
+
+ *cp++ = '\0';
+
+ for (par = params; par->name; par++)
+ {
+ if (strcmp(str, par->name) == 0)
+ break;
+ }
+
+ switch (par->value)
+ {
+ case PAR_IF:
+ if (inFile)
+ {
+ fprintf(stderr, "Multiple input files illegal\n");
+ goto usage;
+ }
+
+ //fprintf(stderr, "if=%s\n", cp);
+ inFile = cp;
+ break;
+
+ case PAR_OF:
+ if (outFile)
+ {
+ fprintf(stderr, "Multiple output files illegal\n");
+ goto usage;
+ }
+
+ //fprintf(stderr, "of=%s\n", cp);
+ outFile = cp;
+ break;
+
+ case PAR_BS:
+ blockSize = getNum(cp);
+ //fprintf(stderr, "bs=%d\n", blockSize);
+
+ if (blockSize <= 0)
+ {
+ fprintf(stderr, "Bad block size value\n");
+ goto usage;
+ }
+
+ break;
+
+ case PAR_COUNT:
+ count = getNum(cp);
+ //fprintf(stderr, "count=%ld\n", count);
+
+ if (count < 0)
+ {
+ fprintf(stderr, "Bad count value\n");
+ goto usage;
+ }
+
+ break;
+
+ default:
+ goto usage;
+ }
+ }
+
+ buf = localBuf;
+
+ if (blockSize > sizeof(localBuf))
+ {
+ buf = malloc(blockSize);
+
+ if (buf == NULL)
+ {
+ fprintf(stderr, "Cannot allocate buffer\n");
+ return 1;
+ }
+ }
+
+ intotal = 0;
+ outTotal = 0;
+
+ if (inFile == NULL)
+ inFd = STDIN;
+ else
+ inFd = open(inFile, 0);
+
+ if (inFd < 0)
+ {
+ perror(inFile);
+
+ if (buf != localBuf)
+ free(buf);
+
+ return 1;
+ }
+
+ if (outFile == NULL)
+ outFd = STDOUT;
+ else
+ outFd = creat(outFile, 0666);
+
+ if (outFd < 0)
+ {
+ perror(outFile);
+ close(inFd);
+
+ if (buf != localBuf)
+ free(buf);
+
+ return 1;
+ }
+
+ while ( outTotal < count*blockSize )
+ {
+ inCc = read(inFd, buf, blockSize);
+ if (inCc < 0) {
+ perror(inFile);
+ goto cleanup;
+ }
+ //fprintf(stderr, "read in =%d\n", inCc);
+ 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;
+ }
+ //fprintf(stderr, "wrote out =%d\n", outCc);
+
+ inCc -= outCc;
+ cp += outCc;
+ outTotal += outCc;
+ //fprintf(stderr, "outTotal=%ld\n", outTotal);
+ }
+ }
+
+ if (inCc < 0)
+ perror(inFile);
+
+cleanup:
+ close(inFd);
+
+ if (close(outFd) < 0)
+ perror(outFile);
+
+ if (buf != localBuf)
+ free(buf);
+
+ printf("%ld+%d records in\n", intotal / blockSize,
+ (intotal % blockSize) != 0);
+
+ printf("%ld+%d records out\n", outTotal / blockSize,
+ (outTotal % blockSize) != 0);
+ return 0;
+usage:
+
+ fprintf(stderr, "%s", dd_usage);
+ return 1;
+}
+
+
+/*
+ * Read a number with a possible multiplier.
+ * Returns -1 if the number format is illegal.
+ */
+static long
+getNum(const char * cp)
+{
+ long value;
+
+ if (!isDecimal(*cp))
+ return -1;
+
+ value = 0;
+
+ while (isDecimal(*cp))
+ value = value * 10 + *cp++ - '0';
+
+ switch (*cp++)
+ {
+ case 'k':
+ value *= 1024;
+ break;
+
+ case 'b':
+ value *= 512;
+ break;
+
+ case 'w':
+ value *= 2;
+ break;
+
+ case '\0':
+ return value;
+
+ default:
+ return -1;
+ }
+
+ if (*cp)
+ return -1;
+
+ return value;
+}
+
+#endif
+/* END CODE */
+