From 50ee8769fa773c010ca9876d73c53d01f2f04a73 Mon Sep 17 00:00:00 2001
From: Jacob <jikomissar@wpi.edu>
Date: Wed, 27 Apr 2016 13:41:51 -0400
Subject: [PATCH] See previous commit.

I did that slightly wrong, not quite sure how. But this one is the most-changed, and all the notes are in the last commit.
---
 csim.c | 60 ++++++++++++++++++++++++++++++++++++++++------------------
 1 file changed, 42 insertions(+), 18 deletions(-)

diff --git a/csim.c b/csim.c
index b57e0de..7346b64 100644
--- a/csim.c
+++ b/csim.c
@@ -54,13 +54,15 @@ int main(int argc, char* argv[])
 			VERBOSE = 1;
 			break;
 		case 's': // 2^s = number of sets
-			set_index_bits = parse_int_arg(optarg, 's');
+			set_index_bits = (uint8_t)parse_int_arg(optarg, 's');
+			set_indices = bits_to_size(set_index_bits);
 			break;
 		case 'E': // associativity - lines per set
 			lines = parse_int_arg(optarg, 'E');
 			break;
 		case 'b': // 2^b = block size
-			block_bits = parse_int_arg(optarg, 'b');
+			block_bits = (uint8_t)parse_int_arg(optarg, 'b');
+			block_size = bits_to_size(block_bits);
 			break;
 		case 't':
 			filename = optarg;
@@ -69,18 +71,18 @@ int main(int argc, char* argv[])
 			print_usage();
 			return 0;
 		default:
-			printf("Usage: ./csim [-hv] -s <number> -E <number> -b <number> -t <file>\n");
-			return 1;
+			bad_usage_error();
 		}
 	}
 	/* If any required arguments were not provided. (argflags != 0b1111) */
-	if (!set_index_bits || !lines || !block_bits || !filename) {
-		printf("Usage: ./csim [-hv] -s <number> -E <number> -b <number> -t <file>\n");
-		return 1;
+	if (!set_indices || !lines || !block_size || !filename) {
+		bad_usage_error();
 	}
 	/* End of argument parsing. */
-	printf("Arguments: %zd, %zd, %zd, %hd, %s\n", set_index_bits, lines, block_bits, VERBOSE, filename);
+	printf("Arguments: s=%hhu, E=%zu, b=%hhu, t=%s, v=%hhu, 2^s=%zd, 2^b=%zu\n", set_index_bits, lines, block_bits, filename, VERBOSE, set_indices, block_size);
 
+
+	/* FILE READING */
 	char buffer[20];
 	FILE* f = fopen(filename, "r");
 	if(!f)
@@ -88,7 +90,7 @@ int main(int argc, char* argv[])
 		printf("Invalid file name: %s", filename);
 		exit(-1);
 	}
-
+	
 	while (fgets(buffer, 20, f))
 	{
 		if (buffer[0] == 'I')
@@ -105,12 +107,13 @@ int main(int argc, char* argv[])
 		printf("%c %ld\n", op, address);
 	}
 
+
 	printSummary(0, 0, 0);
 	return 0;
 }
 
 
-void print_usage()
+void print_usage(void)
 {
 	printf("Usage: ./csim [-hv] -s <number> -E <number> -b <number> -t <file>\n"
 		   "Options:\n"
@@ -121,30 +124,51 @@ void print_usage()
 		   "  -b <number> The number of block bits. Must be a positive integer.\n"
 		   "  -t <file>   Name of the file to read a valgrind trace from.");
 }
+/**
+   Prints the summarized usage and exits with status 1.
+*/
+void bad_usage_error(void)
+{
+	printf("Usage: ./csim [-hv] -s <number> -E <number> -b <number> -t <file>\n");
+	exit(1);
+}
 
 /**
-   Parses a string
+   Parses a string into a size_t.
    @param arg The string to parse.
-   @param opt The option being parsed.
+   @param opt The option being parsed. If 'E', the output can not be 0.
    @return The parsed integer if the argument was an integer.
-   @note Exits if argument is invalid
+   @note Exits if argument is invalid.
  */
 size_t parse_int_arg(char* arg, char opt)
 {
 	char* end;
 	long i = strtol(arg, &end, 0);
 
-	if (!i || *end != '\0') {
+	if (*end != '\0' || (!i && opt=='E')) { // associativity can not be zero
 		printf("Invalid argument \"%s\" for option -%c\n", arg, opt);
-		printf("Usage: ./csim [-hv] -s <number> -E <number> -b <number> -t <file>\n");
-		exit(1);
+		bad_usage_error();
 	}
 	else if (i < 0) {
 		printf("Argument %ld for option %c too small (must be greater than 0)", i, opt);
 		exit(1);
 	}
-	else {
 	return (size_t)i;
-	}
 }
 
+/**
+   Calculates a size using a given number of bits.
+   @param bits The power of 2 to use.
+   @note Exits if number of bits is larger than a size_t.
+ */
+size_t bits_to_size(uint8_t bits)
+{
+	size_t max_shift = 8*sizeof(size_t);
+	if (bits > max_shift-1) {
+		printf("Argument %hhu too large (-s and -b must be less than %zu)", bits, max_shift);
+		exit(1);
+	}
+	return (size_t)1 << bits;
+}
+
+