From 96c4d0e58b5b3cb9775920463f7ff57c4a7dfe35 Mon Sep 17 00:00:00 2001
From: Stathis Kamperis <ekamperi@auth.gr>
Date: Sun, 28 Oct 2007 16:18:14 +0200
Subject: [PATCH] Initial import of hexdump.c file

---
 fileops/hexdump.c | 123 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 123 insertions(+)
 create mode 100644 fileops/hexdump.c

diff --git a/fileops/hexdump.c b/fileops/hexdump.c
new file mode 100644
index 0000000..2ec58f7
--- /dev/null
+++ b/fileops/hexdump.c
@@ -0,0 +1,123 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>    /* for memset() */
+#include <getopt.h>
+
+/* Function prototypes */
+void diep(const char *s);
+void dieu(const char *pname);
+
+#define BUFSIZE 20    /* Must be dividable by 2 */
+
+int main(int argc, char *argv[])
+{
+    unsigned char buf[BUFSIZE + 1];    /* +1 for the '\0' */
+    FILE *fp;
+    int cnt, i, j, len, skip;
+    int readbytes;
+    int caps, opt;
+    int totalbytes = 0;
+    char *fpath;
+
+    /* Parse arguments */
+    caps = 0;
+    len = -1;
+    skip = 0;
+    fpath = NULL;
+    while ((opt = getopt(argc, argv, "Cn:s:f:")) != -1) {
+        switch (opt) {
+        case 'C':
+            caps = 1;
+            break;
+        case 'n':
+            len = atoi(optarg);
+            break;
+        case 's':
+            skip = atoi(optarg);
+            break;
+        case 'f':
+            fpath = optarg;
+            break;
+        default:    /* '?' */
+            dieu(argv[0]);
+        }
+    }
+
+    if (optind < argc) {
+        fprintf(stderr, "non-option argv[]-elements: ");
+        while (optind < argc)
+            fprintf(stderr, "%s ", argv[optind++]);
+        fprintf(stderr, "\n");
+        exit(EXIT_FAILURE);
+    }
+
+    if (fpath == NULL)
+        dieu(argv[0]);
+
+    /* Open file */
+    if ((fp = fopen(fpath, "r")) == NULL)
+        diep("open");
+
+    /* Skip ``skip'' bytes */
+    fseek(fp, skip, SEEK_SET);
+
+    /* Loop */
+    cnt = 0;
+    while(!feof(fp) && (totalbytes < len || len == -1)) {
+        /* Initialize buffer */
+        memset(buf, 0, BUFSIZE);
+
+        /* Read ``BUFSIZE'' elements of 1 byte long from file */
+        readbytes = fread(buf, 1, BUFSIZE, fp);
+
+        /* Print buffer */
+        printf("%08lX  ", (unsigned long)cnt * BUFSIZE + skip);
+        for (i = 0; i < readbytes && (totalbytes < len || len == -1); i++, totalbytes++) {
+            printf("%02X ", buf[i]);
+            if (i == (BUFSIZE / 2) - 1)
+                printf(" ");
+        }
+
+        /* Fill in the blanks */
+        for (j = 0; j < (BUFSIZE - i); j++) {
+            printf("   ");
+            if (j == (BUFSIZE/2) - 1)
+                printf(" ");
+        }
+
+        /*
+         * Print the output characters in the default character set.
+         * Nonprinting characters are displayed as a single ``.''
+         */
+        printf(" |");
+        for (j = 0; j < i; j++) {
+            if (buf[j] >= 32 && buf[j] <= 127)
+                printf("%c", buf[j]);
+            else
+                printf(".");
+        }
+        printf("|");
+
+        /* New line */
+        printf("\n");
+
+        cnt++;
+    }
+
+    /* Close device file */
+    (void)fclose(fp);
+
+    return EXIT_SUCCESS;
+}
+
+void diep(const char *s)
+{
+    perror(s);
+    exit(EXIT_FAILURE);
+}
+
+void dieu(const char *pname)
+{
+    fprintf(stderr, "Usage: %s [-C] [-n length] [-s skip] -f file\n", pname);
+    exit(EXIT_FAILURE);
+}
\ No newline at end of file
-- 
2.11.4.GIT