cmdline.c

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* Inputs:
*    char *name:    name of field, must be non-null if opt_sw == cl_INIT
*    int opt_sw:    option, switch, init, or arg
*    int n:         argument number (if opt_sw is cl_ARG)
* Result:
*    returns pointer to option value/switch if one exists, otherwise null
* Implementation:
*    parse the command line until name or arg is found
*    see if the option is followed by a string that does
*    not start with "-"
*****************************************************************/

private char *cl_search(name, opt_sw, n)
  char *name;
  int opt_sw;
  int n;        /* if opt_sw is cl_ARG, n > 0 tells which one */
{
    register int i = 1;    /* index into command line */
    boolean abbr;
    boolean result = TRUE;

    ready_check();

    /* parse command line: */
    while (i < argc) {
        register char *arg = argv[i];
        /* arguments that start with '-' should be quoted and quotes must
           be removed by the application
         */
        if (*arg == '-') {
            int arg_type = find_string(arg + 1, &abbr);
            if (arg_type == cl_OPT) {
                i += 1; /* skip name and option */
                /* don't look for '-' because the option might be a
                 * negative number
                 */
                if (i >= argc /* || *arg == '-' */) {
                    if (opt_sw == cl_INIT) {
                        gprintf(ERROR, "missing argument after %s\n", arg);
                        result = FALSE;
                    }
                } else if (opt_sw == cl_OPT &&
                    (strcmp(arg + 1, name) == 0 ||
                     (abbr && *(arg + 1) == name[0]))) {
                    return argv[i];
                }
            } else if (arg_type == cl_SW) {
                if (opt_sw == cl_SW &&
                    (strcmp(arg + 1, name) == 0 ||
                     (abbr && *(arg + 1) == name[0])))
                    return arg;
            } else if (opt_sw == cl_INIT)  {
                gprintf(ERROR, "invalid switch: %s\n", arg);
                result = FALSE;
            }
        } else if (opt_sw == cl_ARG) {
            if (n == 1) return arg;
            n--;
        }
        i++; /* skip to next field */
    }
    if (opt_sw == cl_INIT) {
        /* return name or NULL to represent TRUE or FALSE */
        return (result ? name : NULL);
    }
    return NULL;
}

/****************************************************************
*           cl_option
* Inputs:
*    char *name:    option name
* Outputs:
*    returns char *: the option string if found, otherwise null
****************************************************************/

char *cl_option(name)
char *name;
{
    return cl_search(name, cl_OPT, 0);
}

/****************************************************************
*           cl_switch
* Inputs:
*    char *name:    switch name
* Outputs:
*    boolean:    TRUE if switch found
****************************************************************/

boolean cl_switch(name)
char *name;
{
    return (boolean)(cl_search(name, cl_SW, 0) != NULL);
}

/* cl_syntax -- install a string specifying options and switches */
/**/
boolean cl_syntax(char *s)
{
    if (n_syntax < syntax_max) {
        syntax[n_syntax++] = s;
        return TRUE;
    } else {
        gprintf(ERROR, "cl_syntax: out of room\n");
        return FALSE;
    }
}

/****************************************************************
*           find_string
* Inputs:
*    char *s:    string to find, terminated by any non-alphanumeric
*    boolean *abbr: set TRUE if s is an abbreviation, otherwise false
* Effect:
*    Looks for s in syntax strings
* Returns:
*    0 = FALSE = not found, 1 = cl_OPT = option, 2 = cl_SW = switch
*****************************************************************/

private int find_string(s, abbr)
  char *s;
  boolean *abbr;
{
    int found_it = FALSE;
    int i;
    *abbr = FALSE;
    for (i = 0; i < n_syntax; i++) {    /* loop through strings */
        register char *syntax_ptr = syntax[i];
        while (*syntax_ptr != EOS) {
            register char *s_ptr = s;
            while (*syntax_ptr != EOS &&
                   !(isalnum(*syntax_ptr))) syntax_ptr++;
            while (*s_ptr != EOS && (*s_ptr++ == *syntax_ptr))
                syntax_ptr++; /* only increment if there's a match */
            if (!(isalnum(*s_ptr)) && *syntax_ptr == '<') {
                syntax_ptr++; /* advance to the type field */
                if (*syntax_ptr == 's') return cl_SW;
                if (*syntax_ptr != 'o') 
                    gprintf(ERROR,
                            "(internal error) bad cl_syntax string: %s\n",
                            syntax[i]);
                return cl_OPT;
            }
            /* no match, so go to next */
            while (*syntax_ptr != ';' && *syntax_ptr != EOS) syntax_ptr++;
            if (*syntax_ptr == ';') syntax_ptr++;
        }
    }

    /* no match, maybe there is a single character match */
    if (s[0] == EOS || s[1] != EOS) return FALSE;

    for (i = 0; i < n_syntax; i++) {    /* loop through strings */
        char *syntax_ptr = syntax[i];
        while (*syntax_ptr != EOS) {
            while (*syntax_ptr != EOS &&
                   !(isalnum(*syntax_ptr))) syntax_ptr++;
            if (s[0] == *syntax_ptr) {
                if (found_it) return FALSE;     /* ambiguous */
                /* else, find the type */
                while (*syntax_ptr != '<' && *syntax_ptr != EOS)
                    syntax_ptr++;
                syntax_ptr++;
                if (*syntax_ptr == 's') found_it = cl_SW;
                else if (*syntax_ptr == 'o') found_it = cl_OPT;
                else return FALSE;      /* error in string syntax */
            }
            /* no match, so go to next */
            while (*syntax_ptr != ';' && *syntax_ptr != EOS) syntax_ptr++;
            if (*syntax_ptr == ';') syntax_ptr++;
        }
    }
    if (found_it) *abbr = TRUE;
    return found_it;
}


/* get_arg -- get an argument from a file */
/**/
boolean get_arg(file, arg)
  FILE *file;
  char *arg;
{
    int c;
    while ((c = getc(file)) != EOF && isspace(c)) ;
    if (c == EOF) return FALSE;
    ungetc(c, file);
    while ((c = getc(file)) != EOF && !isspace(c)) {
            *arg++ = c;
    }
    *arg = 0;
    return TRUE;
}


/* indirect_command -- get argv, argc from a file */
/**/
private void indirect_command(filename, oldarg0)
  char *filename;
  char *oldarg0;
{
    FILE *argfile = fopen(filename, "r");
    if (!argfile) {
            argv = (char **) malloc(sizeof(char *));
        argv[0] = oldarg0;
        argc = 1;
    } else {
            int i = 1;
        char arg[100];
        while (get_arg(argfile, arg)) i++;
        fclose(argfile);
        argfile = fopen(filename, "r");
        argv = (char **) malloc(sizeof(char *) * i);
        argv[0] = oldarg0;
        argc = i;
        i = 1;
        while (get_arg(argfile, arg)) {
            argv[i] = (char *) malloc(strlen(arg) + 1);
            strcpy(argv[i], arg);
            i++;
        }
    }
}

/****************************************************************
*           ready_check
* Effect:
*    Halt program if cl_rdy is not true.
*****************************************************************/
private void ready_check()
{
    if (!cl_rdy) {
        gprintf(ERROR,
        "Internal error: cl_init was not called, see cmdline.c\n");
        EXIT(1);
    }
}