busybox/coreutils/expand.c

/* expand - convert tabs to spaces
 * unexpand - convert spaces to tabs
 *
 * Copyright (C) 89, 91, 1995-2006 Free Software Foundation, Inc.
 *
 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
 *
 * David MacKenzie <djm@gnu.ai.mit.edu>
 *
 * Options for expand:
 * -t num  --tabs=NUM      Convert tabs to num spaces (default 8 spaces).
 * -i      --initial       Only convert initial tabs on each line to spaces.
 *
 * Options for unexpand:
 * -a      --all           Convert all blanks, instead of just initial blanks.
 * -f      --first-only    Convert only leading sequences of blanks (default).
 * -t num  --tabs=NUM      Have tabs num characters apart instead of 8.
 *
 *  Busybox version (C) 2007 by Tito Ragusa <farmatito@tiscali.it>
 *
 *  Caveat: this versions of expand and unexpand don't accept tab lists.
 */
#include "libbb.h"
#include "unicode.h"

enum {
	OPT_INITIAL     = 1 << 0,
	OPT_TABS        = 1 << 1,
	OPT_ALL         = 1 << 2,
};

#if ENABLE_EXPAND
static void expand(FILE *file, unsigned tab_size, unsigned opt)
{
	char *line;

	while ((line = xmalloc_fgets(file)) != NULL) {
		unsigned char c;
		char *ptr;
		char *ptr_strbeg;

		ptr = ptr_strbeg = line;
		while ((c = *ptr) != '\0') {
			if ((opt & OPT_INITIAL) && !isblank(c)) {
				/* not space or tab */
				break;
			}
			if (c == '\t') {
				unsigned len;
				*ptr = '\0';
# if ENABLE_FEATURE_ASSUME_UNICODE
				len = unicode_strlen(ptr_strbeg);
# else
				len = ptr - ptr_strbeg;
# endif
				len = tab_size - (len % tab_size);
				/*while (ptr[1] == '\t') { ptr++; len += tab_size; } - can handle many tabs at once */
				printf("%s%*s", ptr_strbeg, len, "");
				ptr_strbeg = ptr + 1;
			}
			ptr++;
		}
		fputs(ptr_strbeg, stdout);
		free(line);
	}
}
#endif

#if ENABLE_UNEXPAND
static void unexpand(FILE *file, unsigned tab_size, unsigned opt)
{
	char *line;

	while ((line = xmalloc_fgets(file)) != NULL) {
		char *ptr = line;
		unsigned column = 0;

		while (*ptr) {
			unsigned n;
			unsigned len;

			while (*ptr == ' ') {
				column++;
				ptr++;
			}
			if (*ptr == '\t') {
				column += tab_size - (column % tab_size);
				ptr++;
				continue;
			}

			n = column / tab_size;
			column = column % tab_size;
			while (n--)
				putchar('\t');

			if ((opt & OPT_INITIAL) && ptr != line) {
				printf("%*s%s", column, "", ptr);
				break;
			}
			n = strcspn(ptr, "\t ");
			printf("%*s%.*s", column, "", n, ptr);
# if ENABLE_FEATURE_ASSUME_UNICODE
			{
				char c;
				c = ptr[n];
				ptr[n] = '\0';
				len = unicode_strlen(ptr);
				ptr[n] = c;
			}
# else
			len = n;
# endif
			ptr += n;
			column = (column + len) % tab_size;
		}
		free(line);
	}
}
#endif

int expand_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
int expand_main(int argc UNUSED_PARAM, char **argv)
{
	/* Default 8 spaces for 1 tab */
	const char *opt_t = "8";
	FILE *file;
	unsigned tab_size;
	unsigned opt;
	int exit_status = EXIT_SUCCESS;

#if ENABLE_FEATURE_EXPAND_LONG_OPTIONS
	static const char expand_longopts[] ALIGN1 =
		/* name, has_arg, val */
		"initial\0"          No_argument       "i"
		"tabs\0"             Required_argument "t"
	;
#endif
#if ENABLE_FEATURE_UNEXPAND_LONG_OPTIONS
	static const char unexpand_longopts[] ALIGN1 =
		/* name, has_arg, val */
		"first-only\0"       No_argument       "i"
		"tabs\0"             Required_argument "t"
		"all\0"              No_argument       "a"
	;
#endif
	init_unicode();

	if (ENABLE_EXPAND && (!ENABLE_UNEXPAND || applet_name[0] == 'e')) {
		IF_FEATURE_EXPAND_LONG_OPTIONS(applet_long_options = expand_longopts);
		opt = getopt32(argv, "it:", &opt_t);
	} else {
		IF_FEATURE_UNEXPAND_LONG_OPTIONS(applet_long_options = unexpand_longopts);
		/* -t NUM sets also -a */
		opt_complementary = "ta";
		opt = getopt32(argv, "ft:a", &opt_t);
		/* -f --first-only is the default */
		if (!(opt & OPT_ALL)) opt |= OPT_INITIAL;
	}
	tab_size = xatou_range(opt_t, 1, UINT_MAX);

	argv += optind;

	if (!*argv) {
		*--argv = (char*)bb_msg_standard_input;
	}
	do {
		file = fopen_or_warn_stdin(*argv);
		if (!file) {
			exit_status = EXIT_FAILURE;
			continue;
		}

		if (ENABLE_EXPAND && (!ENABLE_UNEXPAND || applet_name[0] == 'e'))
			IF_EXPAND(expand(file, tab_size, opt));
		else
			IF_UNEXPAND(unexpand(file, tab_size, opt));

		/* Check and close the file */
		if (fclose_if_not_stdin(file)) {
			bb_simple_perror_msg(*argv);
			exit_status = EXIT_FAILURE;
		}
		/* If stdin also clear EOF */
		if (file == stdin)
			clearerr(file);
	} while (*++argv);

	/* Now close stdin also */
	/* (if we didn't read from it, it's a no-op) */
	if (fclose(stdin))
		bb_perror_msg_and_die(bb_msg_standard_input);

	fflush_stdout_and_exit(exit_status);
}
1	niro	816	/* expand - convert tabs to spaces
2			* unexpand - convert spaces to tabs
3			*
4			* Copyright (C) 89, 91, 1995-2006 Free Software Foundation, Inc.
5			*
6			* Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
7			*
8			* David MacKenzie <djm@gnu.ai.mit.edu>
9			*
10			* Options for expand:
11			* -t num --tabs=NUM Convert tabs to num spaces (default 8 spaces).
12			* -i --initial Only convert initial tabs on each line to spaces.
13			*
14			* Options for unexpand:
15			* -a --all Convert all blanks, instead of just initial blanks.
16			* -f --first-only Convert only leading sequences of blanks (default).
17			* -t num --tabs=NUM Have tabs num characters apart instead of 8.
18			*
19			* Busybox version (C) 2007 by Tito Ragusa <farmatito@tiscali.it>
20			*
21			* Caveat: this versions of expand and unexpand don't accept tab lists.
22			*/
23			#include "libbb.h"
24	niro	984	#include "unicode.h"
25	niro	816
26			enum {
27			OPT_INITIAL = 1 << 0,
28			OPT_TABS = 1 << 1,
29			OPT_ALL = 1 << 2,
30			};
31
32			#if ENABLE_EXPAND
33			static void expand(FILE *file, unsigned tab_size, unsigned opt)
34			{
35			char *line;
36
37	niro	984	while ((line = xmalloc_fgets(file)) != NULL) {
38			unsigned char c;
39			char *ptr;
40			char *ptr_strbeg;
41	niro	816
42	niro	984	ptr = ptr_strbeg = line;
43			while ((c = *ptr) != '\0') {
44			if ((opt & OPT_INITIAL) && !isblank(c)) {
45			/* not space or tab */
46			break;
47	niro	816	}
48	niro	984	if (c == '\t') {
49			unsigned len;
50			*ptr = '\0';
51			# if ENABLE_FEATURE_ASSUME_UNICODE
52			len = unicode_strlen(ptr_strbeg);
53			# else
54			len = ptr - ptr_strbeg;
55			# endif
56			len = tab_size - (len % tab_size);
57			/while (ptr[1] == '\t') { ptr++; len += tab_size; } - can handle many tabs at once /
58			printf("%s%*s", ptr_strbeg, len, "");
59			ptr_strbeg = ptr + 1;
60	niro	816	}
61	niro	984	ptr++;
62	niro	816	}
63	niro	984	fputs(ptr_strbeg, stdout);
64			free(line);
65	niro	816	}
66			}
67			#endif
68
69			#if ENABLE_UNEXPAND
70	niro	984	static void unexpand(FILE *file, unsigned tab_size, unsigned opt)
71	niro	816	{
72			char *line;
73
74			while ((line = xmalloc_fgets(file)) != NULL) {
75	niro	984	char *ptr = line;
76			unsigned column = 0;
77
78			while (*ptr) {
79			unsigned n;
80			unsigned len;
81
82			while (*ptr == ' ') {
83	niro	816	column++;
84	niro	984	ptr++;
85	niro	816	}
86	niro	984	if (*ptr == '\t') {
87			column += tab_size - (column % tab_size);
88			ptr++;
89			continue;
90	niro	816	}
91	niro	984
92			n = column / tab_size;
93			column = column % tab_size;
94			while (n--)
95			putchar('\t');
96
97			if ((opt & OPT_INITIAL) && ptr != line) {
98			printf("%*s%s", column, "", ptr);
99			break;
100			}
101			n = strcspn(ptr, "\t ");
102			printf("%s%.s", column, "", n, ptr);
103			# if ENABLE_FEATURE_ASSUME_UNICODE
104			{
105			char c;
106			c = ptr[n];
107			ptr[n] = '\0';
108			len = unicode_strlen(ptr);
109			ptr[n] = c;
110			}
111			# else
112			len = n;
113			# endif
114			ptr += n;
115			column = (column + len) % tab_size;
116	niro	816	}
117	niro	984	free(line);
118	niro	816	}
119			}
120			#endif
121
122			int expand_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
123			int expand_main(int argc UNUSED_PARAM, char **argv)
124			{
125			/* Default 8 spaces for 1 tab */
126			const char *opt_t = "8";
127			FILE *file;
128			unsigned tab_size;
129			unsigned opt;
130			int exit_status = EXIT_SUCCESS;
131
132			#if ENABLE_FEATURE_EXPAND_LONG_OPTIONS
133			static const char expand_longopts[] ALIGN1 =
134			/* name, has_arg, val */
135			"initial\0" No_argument "i"
136			"tabs\0" Required_argument "t"
137			;
138			#endif
139			#if ENABLE_FEATURE_UNEXPAND_LONG_OPTIONS
140			static const char unexpand_longopts[] ALIGN1 =
141			/* name, has_arg, val */
142			"first-only\0" No_argument "i"
143			"tabs\0" Required_argument "t"
144			"all\0" No_argument "a"
145			;
146			#endif
147	niro	984	init_unicode();
148	niro	816
149			if (ENABLE_EXPAND && (!ENABLE_UNEXPAND \|\| applet_name[0] == 'e')) {
150	niro	984	IF_FEATURE_EXPAND_LONG_OPTIONS(applet_long_options = expand_longopts);
151	niro	816	opt = getopt32(argv, "it:", &opt_t);
152			} else {
153	niro	984	IF_FEATURE_UNEXPAND_LONG_OPTIONS(applet_long_options = unexpand_longopts);
154	niro	816	/* -t NUM sets also -a */
155			opt_complementary = "ta";
156			opt = getopt32(argv, "ft:a", &opt_t);
157			/* -f --first-only is the default */
158			if (!(opt & OPT_ALL)) opt \|= OPT_INITIAL;
159			}
160			tab_size = xatou_range(opt_t, 1, UINT_MAX);
161
162			argv += optind;
163
164			if (!*argv) {
165			--argv = (char)bb_msg_standard_input;
166			}
167			do {
168			file = fopen_or_warn_stdin(*argv);
169			if (!file) {
170			exit_status = EXIT_FAILURE;
171			continue;
172			}
173
174			if (ENABLE_EXPAND && (!ENABLE_UNEXPAND \|\| applet_name[0] == 'e'))
175	niro	984	IF_EXPAND(expand(file, tab_size, opt));
176	niro	816	else
177	niro	984	IF_UNEXPAND(unexpand(file, tab_size, opt));
178	niro	816
179			/* Check and close the file */
180			if (fclose_if_not_stdin(file)) {
181			bb_simple_perror_msg(*argv);
182			exit_status = EXIT_FAILURE;
183			}
184			/* If stdin also clear EOF */
185			if (file == stdin)
186			clearerr(file);
187			} while (*++argv);
188
189			/* Now close stdin also */
190			/* (if we didn't read from it, it's a no-op) */
191			if (fclose(stdin))
192			bb_perror_msg_and_die(bb_msg_standard_input);
193
194			fflush_stdout_and_exit(exit_status);
195			}