#include "spsh.h"

/* Process a read line into a command and arguments and try to execute it */
void cmd(char *line) {
    char *cmd, *cmd_arg;
    pid_t pid;
    int status, cmd_argc;
    char *cmd_argv[MAX_ARGS];

    /* First argument is always the executable file itself; we make it NULL to
     * start with, and then terminate the array with NULL */
    cmd_argv[0] = cmd_argv[1] = NULL;
    cmd_argc = 1;

    /* Read the command as the first token of the line */
    cmd = strtok(line, ARG_DELIM);

    /* Iterate through the remaining arguments with subsequent calls to strtok() */
    while ((cmd_arg = strtok(NULL, ARG_DELIM)) != NULL) {
        cmd_argc++;
        if (cmd_argc < MAX_ARGS) {
            cmd_argv[cmd_argc - 1] = cmd_arg;
            cmd_argv[cmd_argc] = NULL;
        }
    }

    /* If there were too many arguments, say so */
    if (cmd_argc >= MAX_ARGS) {
        fprintf(stderr, "Too many arguments (%u given, max is %u)\n", cmd_argc, MAX_ARGS);
        return;
    }

    /* Fork and try to execute it; wait until the fork is done. */
    pid = fork();
    if (pid == 0) {
        cmd_argv[0] = cmd;
        execvp(cmd, cmd_argv);
    }
    waitpid(pid, &status, 0);

    return;
}