Added more commnets (62b4a6d0) · Commits · coms352 / shell

main.c

+28 −2

Original line number	Diff line number	Diff line
		@@ -39,36 +39,53 @@ int main() {
		exit(EXIT_SUCCESS);
		}

		// Figure out if we need to pipe things
		char *doMore = strchr(readBuff, '\|');
		if (doMore != NULL) {
		readBuff = strtok(readBuff, "\|");
		}
		// Max of 10 commands in ; chains
		char commands[10][BUFFSIZE];
		int numCmds = 0;
		// If we have many command add them to the
		// command array
		char *doMany = strchr(readBuff, ';');
		if (doMany != NULL) {
		// Don't overrun the array
		if (numCmds >= 10) {
		break;
		}
		// Make it thread safe
		char *strtok_save;
		// ; seperate commands
		char *del = ";";
		// First time
		char * cmdTok = strtok_r(readBuff, del, &strtok_save);
		strcpy(commands[0], cmdTok);
		numCmds = 1;
		while (cmdTok != NULL) {
		// Per the docs null for all other calls to strtok_r
		cmdTok = strtok_r(NULL, del, &strtok_save);
		// Don't segfault
		// Do while might be better?
		if (cmdTok == NULL) {
		break;
		}
		// Copy to commands array
		strcpy(commands[numCmds], cmdTok);
		// We got one more command
		numCmds++;
		}

		} else {
		// Default for one command
		strcpy(commands[0], readBuff);
		numCmds = 1;
		}

		// Run this loop for each command
		// This supports commands like the following:
		// date;ls;cal;ps
		for (int i = 0; i < numCmds; i++) {
		char *tokens = malloc(sizeof(char) 5000);
		int numTokens = tokenize(commands[i], tokens);
		@@ -93,6 +110,7 @@ int main() {
		}
		}

		// Logic for history
		if (strcmp(tokens[0], "history") == 0) {
		if (historyPos == -1) {
		fprintf(stderr, "\nNo commands in history\n");
		@@ -108,7 +126,7 @@ int main() {
		continue;
		}


		// Logic for !!
		if (strcmp(tokens[0], "!!") == 0) {
		if (historyPos == -1) {
		fprintf(stderr, "\nbsh: No such command in history.\n");
		@@ -120,6 +138,8 @@ int main() {
		}
		}


		// Logic for !N
		char *ptr;
		if (*tokens[0] == '!' && strcmp(tokens[0], "!!") != 0) {
		errno = 0;
		@@ -163,20 +183,26 @@ int main() {
		// https://stackoverflow.com/a/13803962
		if (fork() == 0) {
		if (doMoreCheck != 0) {
		// Close stdout
		close(STDOUT_FILENO);
		// DUP stdout to the pipe
		dup(thePipe[1]);
		// Close the pipes
		close(thePipe[0]);
		close(thePipe[1]);
		}
		// exec it!
		int returnCode = execvp(tokens[0], tokens);
		if (returnCode == -1) {
		// Command not found
		// Let the user know
		fprintf(stdout, "bsh: Command not found\n");
		}
		// Clean up and we are done;
		printf("\n");
		exit(1);
		} else {
		// Wait where if no & and not a pipe
		// Wait where if no "&" and not a pipe
		if (runInBackground == 0 && doMoreCheck == 0) {
		wait(NULL);
		}