int main(void)
{
/* 0(bin) have length 1, so r[0] should be 1 */
int bin_max[18] = { 1, 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048, 4096, 8192, 16384, 32768, 65536 };
int bin_len[18] = { 0, };
for(int i = 0; i < 131072; i++)
{
char bin[18] = {0, };
int len = convert_decimal_to_binary(i, bin);
if(strstr(bin, "00") != NULL) bin_len[len]++;
}
for(int i = 0; i < 18; i++)
printf("%d: %d\n", i, bin_max[i] - bin_len[i]);
return 0;
}
/**************************************************************************
* Main driver of the program. *
**************************************************************************/
int main(int argc, char **argv)
{
if(argc != 3) {
printf("Usage: $ %s input_a input_b\n", argv[0]);
return -1;
}
#ifdef DIAG
printf("Starting program...\n");
sleep(1);
#endif
// Declare variables.
pid_t pid;
FILE *vector_a, *vector_b, *output;
int pipe1_fd[2], pipe2_fd[2], length;;
long long decimal_value, decimal_value2;
char input_a[MAX_VECTOR_SIZE], input_b[MAX_VECTOR_SIZE];
// Open input and output files.
vector_a = fopen(argv[1], "r");
vector_b = fopen(argv[2], "r");
output = fopen("output.txt", "w");
// Create pipes.
if(pipe(pipe1_fd)) {
perror("Plumbing problem.\n");
exit(1);
}
if(pipe(pipe2_fd)) {
perror("Plumbing problem.\n");
exit(1);
}
pid = fork();
if(pid < 0) {
fprintf(stderr, "First fork() failed.\n");
return(1);
} else if(pid) {
pid = fork();
if(pid < 0) {
fprintf(stderr, "Second fork() failed.\n");
return(1);
} else if(pid) {
// Process 2
#ifdef DIAG
printf("Process 2 created.\n");
sleep(2);
#endif
close(pipe1_fd[PIPE_READ]); // Close the read portion of pipe 1.
close(pipe1_fd[PIPE_WRITE]); // Close the write portion of pipe 1.
close(pipe2_fd[PIPE_WRITE]); // Close the write portion of pipe 2.
while(fgets(input_a, MAX_VECTOR_SIZE, vector_a) != NULL) {
// Reads in and process input_a line by line.
char *position;
if((position = strchr(input_a, '\n')) != NULL) {
*position = '\0'; // Removes newline character from end of buffer.
}
#ifdef DIAG
printf("Process 2: Read line '%s' from input_a file.\n", input_a);
#endif
length = strlen(input_a); // Get the length in bits of input_a.
decimal_value = convert_binary_to_decimal(input_a); // Convert the binary number to decimal for easier math.
#ifdef DIAG
printf("Process 2: Converted '%s' to integer value %lld.\n", input_a, decimal_value);
#endif
read(pipe2_fd[PIPE_READ], input_b, sizeof(input_b)); // Reads in the two's complimented input_b from the pipe.
#ifdef DIAG
printf("Process 2: Read '%s' from pipe 2.\n", input_b);
#endif
decimal_value2 = strtoll(input_b, NULL, 10); // Convert the binary number to decimal for easier math.
#ifdef DIAG
printf("Process 2: Converted '%s' to integer value %lld.\n", input_b, decimal_value2);
#endif
decimal_value += decimal_value2; // Add input_a with input_b.
#ifdef DIAG
printf("Process 2: Added %lld with %lld to get %lld.\n", decimal_value - decimal_value2, decimal_value2, decimal_value);
#endif
convert_decimal_to_binary(output, decimal_value, length); // Convert the decimal number back to a binary string.
#ifdef DIAG
printf("Process 2: Converting %lld to binary and writing to file \"output.txt\".\n", decimal_value);
#endif
#ifdef DIAG
sleep(3);
#endif
}
#ifdef DIAG
printf("Process 2: No more input, closing pipe and exiting.\n");
#endif
close(pipe2_fd[PIPE_READ]); // Close the read portion of pipe 2.
exit(0);
} else {
// Process 1
#ifdef DIAG
printf("Process 1 created.\n");
sleep(2);
#endif
close(pipe1_fd[PIPE_WRITE]); // Close the write portion of pipe 1.
close(pipe2_fd[PIPE_READ]); // Close the read portion of pipe 2.
while(read(pipe1_fd[PIPE_READ], input_b, sizeof(input_b))) {
#ifdef DIAG
printf("Process 1: Read '%s' from pipe 1.\n", input_b);
#endif
decimal_value = convert_binary_to_decimal(input_b); // Convert the binary number to decimal for easier math.
#ifdef DIAG
printf("Process 1: Converted '%s' to integer value %lld.\n", input_b, decimal_value);
#endif
decimal_value++; // Increments the decimal value by 1.
#ifdef DIAG
printf("Process 1: Incremented by 1 to %lld.\n", decimal_value);
#endif
sprintf(input_b, "%lld", decimal_value); // Convert from long long to string.
#ifdef DIAG
printf("Process 1: Writing to pipe 2.\n");
#endif
// Write the incremented number to the pipe.
write(pipe2_fd[PIPE_WRITE], (const void *) input_b, (size_t) strlen(input_b) + 1);
#ifdef DIAG
sleep(3);
#endif
}
#ifdef DIAG
printf("Process 1: No more input, closing pipes and exiting.\n");
#endif
close(pipe1_fd[PIPE_READ]); // Close the read portion of pipe 1.
close(pipe2_fd[PIPE_WRITE]); // Close the write portion of pipe 2.
exit(0);
}
} else {
// Process 0
#ifdef DIAG
printf("Process 0 created.\n");
sleep(2);
#endif
close(pipe1_fd[PIPE_READ]); // Close the read portion of pipe 1.
close(pipe2_fd[PIPE_READ]); // Close the read portion of pipe 2.
close(pipe2_fd[PIPE_WRITE]); // Close the write portion of pipe 2.
while(fgets(input_b, MAX_VECTOR_SIZE, vector_b) != NULL) {
// Reads in and processes input_b line by line.
char *position;
if((position = strchr(input_b, '\n')) != NULL) {
*position = '\0'; // Removes newline character from end of buffer.
}
#ifdef DIAG
printf("Process 0: Read line '%s' from input_b file.\n", input_b);
#endif
complementer(input_b); // Bitwise complement on the binary number.
#ifdef DIAG
printf("Process 0: Complemented input to '%s'.\n", input_b);
#endif
// Write the complemented number to the pipe.
#ifdef DIAG
printf("Process 0: Writing to pipe 1.\n");
#endif
write(pipe1_fd[PIPE_WRITE], (const void *) input_b, (size_t) strlen(input_b) + 1);
#ifdef DIAG
sleep(3);
#endif
}
#ifdef DIAG
printf("Process 0: No more input, closing pipe and exiting.\n");
#endif
close(pipe1_fd[PIPE_WRITE]); // Close the write portion of pipe 1.
exit(0);
}
return 0;
}
