[unix-history] / usr.bin / more / filename.c

/*
 * Expand a string, substituting any "%" with the current filename,
 * and any "#" with the previous filename and an initial "!" with 
 * the second string.
 */
char *
fexpand(s, t)
	char *s;
	char *t;
{
	extern char *current_file, *previous_file;
	register char *fr, *to;
	register int n;
	register char *e;

	if (*s == '\0')
		return ((char *) 0);
	/*
	 * Make one pass to see how big a buffer we 
	 * need to allocate for the expanded string.
	 */
	n = 0;
	for (fr = s;  *fr != '\0';  fr++)
	{
		switch (*fr)
		{
		case '!':
			if (s == fr && t == (char *) 0) {
				error("no previous command");
				return ((char *) 0);
			}
			n += (s == fr) ? strlen(t) : 1;
			break;
		case '%':
			n += (current_file != (char *) 0) ?  
			     strlen(current_file) : 1;
			break;
		case '#':
			n += (previous_file != (char *) 0) ?  
			     strlen(previous_file) : 1;
			break;
		default:
			n++;
			if (*fr == '\\') {
				n++;
				if (*++fr == '\0') {
					error("syntax error");
					return ((char *) 0);
				}
			}
			break;
		}
	}

	if ((e = (char *) calloc(n+1, sizeof(char))) == (char *) 0) {
		error("cannot allocate memory");
		quit();
	}

	/*
	 * Now copy the string, expanding any "%" or "#".
	 */
	to = e;
	for (fr = s;  *fr != '\0';  fr++)
	{
		switch (*fr)
		{
		case '!':
			if (s == fr) {
				strcpy(to, t);
				to += strlen(to);
			} else
				*to++ = *fr;
			break;
		case '%':
			if (current_file == (char *) 0)
				*to++ = *fr;
			else {
				strcpy(to, current_file);
				to += strlen(to);
			}
			break;
		case '#':
			if (previous_file == (char *) 0)
				*to++ = *fr;
			else {
				strcpy(to, previous_file);
				to += strlen(to);
			}
			break;
		default:
			*to++ = *fr;
			if (*fr == '\\')
				*to++ = *++fr;
			break;
		}
	}
	*to = '\0';
	return (e);
}
Commit	Line	Data
78ed81a3	1	/*
	2	* Expand a string, substituting any "%" with the current filename,
	3	* and any "#" with the previous filename and an initial "!" with
	4	* the second string.
	5	*/
	6	char *
	7	fexpand(s, t)
	8	char *s;
	9	char *t;
	10	{
	11	extern char current_file, previous_file;
	12	register char fr, to;
	13	register int n;
	14	register char *e;
	15
	16	if (*s == '\0')
	17	return ((char *) 0);
	18	/*
	19	* Make one pass to see how big a buffer we
	20	* need to allocate for the expanded string.
	21	*/
	22	n = 0;
	23	for (fr = s; *fr != '\0'; fr++)
	24	{
	25	switch (*fr)
	26	{
	27	case '!':
	28	if (s == fr && t == (char *) 0) {
	29	error("no previous command");
	30	return ((char *) 0);
	31	}
	32	n += (s == fr) ? strlen(t) : 1;
	33	break;
	34	case '%':
	35	n += (current_file != (char *) 0) ?
	36	strlen(current_file) : 1;
	37	break;
	38	case '#':
	39	n += (previous_file != (char *) 0) ?
	40	strlen(previous_file) : 1;
	41	break;
	42	default:
	43	n++;
	44	if (*fr == '\\') {
	45	n++;
	46	if (*++fr == '\0') {
	47	error("syntax error");
	48	return ((char *) 0);
	49	}
	50	}
	51	break;
	52	}
	53	}
	54
	55	if ((e = (char ) calloc(n+1, sizeof(char))) == (char ) 0) {
	56	error("cannot allocate memory");
	57	quit();
	58	}
	59
	60	/*
	61	* Now copy the string, expanding any "%" or "#".
	62	*/
	63	to = e;
	64	for (fr = s; *fr != '\0'; fr++)
65	{
66	switch (*fr)
67	{
68	case '!':
69	if (s == fr) {
70	strcpy(to, t);
71	to += strlen(to);
72	} else
73	to++ = fr;
74	break;
75	case '%':
76	if (current_file == (char *) 0)
77	to++ = fr;
78	else {
79	strcpy(to, current_file);
80	to += strlen(to);
81	}
82	break;
83	case '#':
84	if (previous_file == (char *) 0)
85	to++ = fr;
86	else {
87	strcpy(to, previous_file);
88	to += strlen(to);
89	}
90	break;
91	default:
92	to++ = fr;
93	if (*fr == '\\')
94	to++ = ++fr;
95	break;
96	}
97	}
98	*to = '\0';
99	return (e);
100	}