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1 files changed, 34 insertions, 17 deletions

diff --git a/command/dd.c b/command/dd.c
index e298c69..d628f9f 100644
--- a/command/dd.c
+++ b/command/dd.c
@@ -1,8 +1,17 @@
+/**
+ *  file: dd.c
+ *  command: dd
+ *  author: Tyler Murphy
+ */
+
 #include "command.h"
 #include "lslib.h"
 
 #include <stdlib.h>
 
+/**
+ * Help function for dd
+ */
 static void help(void) {
     printf("Usage: dd [if=FILE] [of=FILE] [bs=N] [count=N]\n\n");
     printf("Copy a file with converting and formatting\n\n");
@@ -12,49 +21,57 @@ static void help(void) {
     printf("\tcount=N\t\tCopy only N input blocks\n");
 }
 
+/**
+* Copys a file with converting and formatting
+*/
 COMMAND(dd_main) {
 
-    FILE* in_file = stdin;
-    FILE* out_file = stdout;
-    int bs = 1024;
-    int count = -1;
+    FILE* in_file = stdin; /* the file to copy from */
+    FILE* out_file = stdout; /* the file to copy to */
+    int bs = 1024; /* the default bs */
+    int count = -1; /* amount of bs's to copy, if negative go until EOF */
     int i;
-    char* buffer;
+    char* buffer; /* buffer to hold copy data */
     size_t read;
 
+    /* parse arguments and only check for --help */
     parse_help(argc, argv, help);
 
+    /* dd doesnt use standard arguments, parse though each argument and match each arg */
     for (i = 0; i < argc; i++) {
-        if (prefix("if=", argv[i])) {
-            char* path = argv[i] + 3;
+        if (prefix("if=", argv[i])) { /* sets the input file */
+            char* path = argv[i] + 3; /* get data after = */
             in_file = get_file(path, "rb");
-        } else if (prefix("of=", argv[i])) {
-            char* path = argv[i] + 3;
+        } else if (prefix("of=", argv[i])) { /* sets the output file */
+            char* path = argv[i] + 3; /* get data after = */
             out_file = get_file(path, "wb");
-        } else if (prefix("bs=", argv[i])) {
-            char* str = argv[i] + 3;
-            bs = get_number(str);
-            if (bs < 1) {
+        } else if (prefix("bs=", argv[i])) { /* sets the blocksize */
+            char* str = argv[i] + 3; /* get data after = */
+            bs = get_blkm(str);
+            if (bs < 1) { /* cannot have a negative bs */
                 error("block size must be greater than 0");
             }
-        } else if (prefix("count=", argv[i])) {
-            char* str = argv[i] + 6;
+        } else if (prefix("count=", argv[i])) { /* sets the count of bs to do */
+            char* str = argv[i] + 6; /* get data after = */
             count = get_number(str);
             if (count < 1) {
                 error("count must be greather than 0");
             }
-        } else {
+        } else { /* error and exit since arg is invalid */
             error("unkown option %s", argv[i]);
         }
     }
- 
+
+    /* allocate buffer of set bs */
     buffer = xalloc(bs);
     
+    /* read data until EOF from and to buf */
     while ((read = fread(buffer, 1, bs, in_file)) != 0) {
         fwrite(buffer, 1, read, out_file);
         if (--count, count == 0) break;
     }
 
+    /* cleanup */
     free(buffer);
     fclose(in_file);
     fclose(out_file);