busybox/libbb/xfuncs.c

/* vi: set sw=4 ts=4: */
/*
 * Utility routines.
 *
 * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
 * Copyright (C) 2006 Rob Landley
 * Copyright (C) 2006 Denys Vlasenko
 *
 * Licensed under GPL version 2, see file LICENSE in this tarball for details.
 */

/* We need to have separate xfuncs.c and xfuncs_printf.c because
 * with current linkers, even with section garbage collection,
 * if *.o module references any of XXXprintf functions, you pull in
 * entire printf machinery. Even if you do not use the function
 * which uses XXXprintf.
 *
 * xfuncs.c contains functions (not necessarily xfuncs)
 * which do not pull in printf, directly or indirectly.
 * xfunc_printf.c contains those which do.
 *
 * TODO: move xmalloc() and xatonum() here.
 */

#include "libbb.h"

/* Turn on nonblocking I/O on a fd */
int FAST_FUNC ndelay_on(int fd)
{
	return fcntl(fd, F_SETFL, fcntl(fd,F_GETFL) | O_NONBLOCK);
}

int FAST_FUNC ndelay_off(int fd)
{
	return fcntl(fd, F_SETFL, fcntl(fd,F_GETFL) & ~O_NONBLOCK);
}

int FAST_FUNC close_on_exec_on(int fd)
{
	return fcntl(fd, F_SETFD, FD_CLOEXEC);
}

/* Convert unsigned long long value into compact 4-char
 * representation. Examples: "1234", "1.2k", " 27M", "123T"
 * String is not terminated (buf[4] is untouched) */
void FAST_FUNC smart_ulltoa4(unsigned long long ul, char buf[5], const char *scale)
{
	const char *fmt;
	char c;
	unsigned v, u, idx = 0;

	if (ul > 9999) { // do not scale if 9999 or less
		ul *= 10;
		do {
			ul /= 1024;
			idx++;
		} while (ul >= 10000);
	}
	v = ul; // ullong divisions are expensive, avoid them

	fmt = " 123456789";
	u = v / 10;
	v = v % 10;
	if (!idx) {
		// 9999 or less: use "1234" format
		// u is value/10, v is last digit
		c = buf[0] = " 123456789"[u/100];
		if (c != ' ') fmt = "0123456789";
		c = buf[1] = fmt[u/10%10];
		if (c != ' ') fmt = "0123456789";
		buf[2] = fmt[u%10];
		buf[3] = "0123456789"[v];
	} else {
		// u is value, v is 1/10ths (allows for 9.2M format)
		if (u >= 10) {
			// value is >= 10: use "123M', " 12M" formats
			c = buf[0] = " 123456789"[u/100];
			if (c != ' ') fmt = "0123456789";
			v = u % 10;
			u = u / 10;
			buf[1] = fmt[u%10];
		} else {
			// value is < 10: use "9.2M" format
			buf[0] = "0123456789"[u];
			buf[1] = '.';
		}
		buf[2] = "0123456789"[v];
		buf[3] = scale[idx]; /* typically scale = " kmgt..." */
	}
}

/* Convert unsigned long long value into compact 5-char representation.
 * String is not terminated (buf[5] is untouched) */
void FAST_FUNC smart_ulltoa5(unsigned long long ul, char buf[6], const char *scale)
{
	const char *fmt;
	char c;
	unsigned v, u, idx = 0;

	if (ul > 99999) { // do not scale if 99999 or less
		ul *= 10;
		do {
			ul /= 1024;
			idx++;
		} while (ul >= 100000);
	}
	v = ul; // ullong divisions are expensive, avoid them

	fmt = " 123456789";
	u = v / 10;
	v = v % 10;
	if (!idx) {
		// 99999 or less: use "12345" format
		// u is value/10, v is last digit
		c = buf[0] = " 123456789"[u/1000];
		if (c != ' ') fmt = "0123456789";
		c = buf[1] = fmt[u/100%10];
		if (c != ' ') fmt = "0123456789";
		c = buf[2] = fmt[u/10%10];
		if (c != ' ') fmt = "0123456789";
		buf[3] = fmt[u%10];
		buf[4] = "0123456789"[v];
	} else {
		// value has been scaled into 0..9999.9 range
		// u is value, v is 1/10ths (allows for 92.1M format)
		if (u >= 100) {
			// value is >= 100: use "1234M', " 123M" formats
			c = buf[0] = " 123456789"[u/1000];
			if (c != ' ') fmt = "0123456789";
			c = buf[1] = fmt[u/100%10];
			if (c != ' ') fmt = "0123456789";
			v = u % 10;
			u = u / 10;
			buf[2] = fmt[u%10];
		} else {
			// value is < 100: use "92.1M" format
			c = buf[0] = " 123456789"[u/10];
			if (c != ' ') fmt = "0123456789";
			buf[1] = fmt[u%10];
			buf[2] = '.';
		}
		buf[3] = "0123456789"[v];
		buf[4] = scale[idx]; /* typically scale = " kmgt..." */
	}
}


// Convert unsigned integer to ascii, writing into supplied buffer.
// A truncated result contains the first few digits of the result ala strncpy.
// Returns a pointer past last generated digit, does _not_ store NUL.
void BUG_sizeof_unsigned_not_4(void);
char* FAST_FUNC utoa_to_buf(unsigned n, char *buf, unsigned buflen)
{
	unsigned i, out, res;
	if (sizeof(unsigned) != 4)
		BUG_sizeof_unsigned_not_4();
	if (buflen) {
		out = 0;
		for (i = 1000000000; i; i /= 10) {
			res = n / i;
			if (res || out || i == 1) {
				if (!--buflen) break;
				out++;
				n -= res*i;
				*buf++ = '0' + res;
			}
		}
	}
	return buf;
}

/* Convert signed integer to ascii, like utoa_to_buf() */
char* FAST_FUNC itoa_to_buf(int n, char *buf, unsigned buflen)
{
	if (buflen && n < 0) {
		n = -n;
		*buf++ = '-';
		buflen--;
	}
	return utoa_to_buf((unsigned)n, buf, buflen);
}

// The following two functions use a static buffer, so calling either one a
// second time will overwrite previous results.
//
// The largest 32 bit integer is -2 billion plus null terminator, or 12 bytes.
// It so happens that sizeof(int) * 3 is enough for 32+ bits.
// (sizeof(int) * 3 + 2 is correct for any width, even 8-bit)

static char local_buf[sizeof(int) * 3];

// Convert unsigned integer to ascii using a static buffer (returned).
char* FAST_FUNC utoa(unsigned n)
{
	*(utoa_to_buf(n, local_buf, sizeof(local_buf))) = '\0';

	return local_buf;
}

/* Convert signed integer to ascii using a static buffer (returned). */
char* FAST_FUNC itoa(int n)
{
	*(itoa_to_buf(n, local_buf, sizeof(local_buf))) = '\0';

	return local_buf;
}

/* Emit a string of hex representation of bytes */
char* FAST_FUNC bin2hex(char *p, const char *cp, int count)
{
	while (count) {
		unsigned char c = *cp++;
		/* put lowercase hex digits */
		*p++ = 0x20 | bb_hexdigits_upcase[c >> 4];
		*p++ = 0x20 | bb_hexdigits_upcase[c & 0xf];
		count--;
	}
	return p;
}

/* Return how long the file at fd is, if there's any way to determine it. */
#ifdef UNUSED
off_t FAST_FUNC fdlength(int fd)
{
	off_t bottom = 0, top = 0, pos;
	long size;

	// If the ioctl works for this, return it.

	if (ioctl(fd, BLKGETSIZE, &size) >= 0) return size*512;

	// FIXME: explain why lseek(SEEK_END) is not used here!

	// If not, do a binary search for the last location we can read.  (Some
	// block devices don't do BLKGETSIZE right.)

	do {
		char temp;

		pos = bottom + (top - bottom) / 2;

		// If we can read from the current location, it's bigger.

		if (lseek(fd, pos, SEEK_SET)>=0 && safe_read(fd, &temp, 1)==1) {
			if (bottom == top) bottom = top = (top+1) * 2;
			else bottom = pos;

		// If we can't, it's smaller.

		} else {
			if (bottom == top) {
				if (!top) return 0;
				bottom = top/2;
			}
			else top = pos;
		}
	} while (bottom + 1 != top);

	return pos + 1;
}
#endif

/* It is perfectly ok to pass in a NULL for either width or for
 * height, in which case that value will not be set.  */
int FAST_FUNC get_terminal_width_height(int fd, unsigned *width, unsigned *height)
{
	struct winsize win = { 0, 0, 0, 0 };
	int ret = ioctl(fd, TIOCGWINSZ, &win);

	if (height) {
		if (!win.ws_row) {
			char *s = getenv("LINES");
			if (s) win.ws_row = atoi(s);
		}
		if (win.ws_row <= 1 || win.ws_row >= 30000)
			win.ws_row = 24;
		*height = (int) win.ws_row;
	}

	if (width) {
		if (!win.ws_col) {
			char *s = getenv("COLUMNS");
			if (s) win.ws_col = atoi(s);
		}
		if (win.ws_col <= 1 || win.ws_col >= 30000)
			win.ws_col = 80;
		*width = (int) win.ws_col;
	}

	return ret;
}

int FAST_FUNC tcsetattr_stdin_TCSANOW(const struct termios *tp)
{
	return tcsetattr(STDIN_FILENO, TCSANOW, tp);
}
1	/* vi: set sw=4 ts=4: */
2	/*
3	* Utility routines.
4	*
5	* Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
6	* Copyright (C) 2006 Rob Landley
7	* Copyright (C) 2006 Denys Vlasenko
8	*
9	* Licensed under GPL version 2, see file LICENSE in this tarball for details.
10	*/
11
12	/* We need to have separate xfuncs.c and xfuncs_printf.c because
13	* with current linkers, even with section garbage collection,
14	* if *.o module references any of XXXprintf functions, you pull in
15	* entire printf machinery. Even if you do not use the function
16	* which uses XXXprintf.
17	*
18	* xfuncs.c contains functions (not necessarily xfuncs)
19	* which do not pull in printf, directly or indirectly.
20	* xfunc_printf.c contains those which do.
21	*
22	* TODO: move xmalloc() and xatonum() here.
23	*/
24
25	#include "libbb.h"
26
27	/* Turn on nonblocking I/O on a fd */
28	int FAST_FUNC ndelay_on(int fd)
29	{
30	return fcntl(fd, F_SETFL, fcntl(fd,F_GETFL) \| O_NONBLOCK);
31	}
32
33	int FAST_FUNC ndelay_off(int fd)
34	{
35	return fcntl(fd, F_SETFL, fcntl(fd,F_GETFL) & ~O_NONBLOCK);
36	}
37
38	int FAST_FUNC close_on_exec_on(int fd)
39	{
40	return fcntl(fd, F_SETFD, FD_CLOEXEC);
41	}
42
43	/* Convert unsigned long long value into compact 4-char
44	* representation. Examples: "1234", "1.2k", " 27M", "123T"
45	* String is not terminated (buf[4] is untouched) */
46	void FAST_FUNC smart_ulltoa4(unsigned long long ul, char buf[5], const char *scale)
47	{
48	const char *fmt;
49	char c;
50	unsigned v, u, idx = 0;
51
52	if (ul > 9999) { // do not scale if 9999 or less
53	ul *= 10;
54	do {
55	ul /= 1024;
56	idx++;
57	} while (ul >= 10000);
58	}
59	v = ul; // ullong divisions are expensive, avoid them
60
61	fmt = " 123456789";
62	u = v / 10;
63	v = v % 10;
64	if (!idx) {
65	// 9999 or less: use "1234" format
66	// u is value/10, v is last digit
67	c = buf[0] = " 123456789"[u/100];
68	if (c != ' ') fmt = "0123456789";
69	c = buf[1] = fmt[u/10%10];
70	if (c != ' ') fmt = "0123456789";
71	buf[2] = fmt[u%10];
72	buf[3] = "0123456789"[v];
73	} else {
74	// u is value, v is 1/10ths (allows for 9.2M format)
75	if (u >= 10) {
76	// value is >= 10: use "123M', " 12M" formats
77	c = buf[0] = " 123456789"[u/100];
78	if (c != ' ') fmt = "0123456789";
79	v = u % 10;
80	u = u / 10;
81	buf[1] = fmt[u%10];
82	} else {
83	// value is < 10: use "9.2M" format
84	buf[0] = "0123456789"[u];
85	buf[1] = '.';
86	}
87	buf[2] = "0123456789"[v];
88	buf[3] = scale[idx]; /* typically scale = " kmgt..." */
89	}
90	}
91
92	/* Convert unsigned long long value into compact 5-char representation.
93	* String is not terminated (buf[5] is untouched) */
94	void FAST_FUNC smart_ulltoa5(unsigned long long ul, char buf[6], const char *scale)
95	{
96	const char *fmt;
97	char c;
98	unsigned v, u, idx = 0;
99
100	if (ul > 99999) { // do not scale if 99999 or less
101	ul *= 10;
102	do {
103	ul /= 1024;
104	idx++;
105	} while (ul >= 100000);
106	}
107	v = ul; // ullong divisions are expensive, avoid them
108
109	fmt = " 123456789";
110	u = v / 10;
111	v = v % 10;
112	if (!idx) {
113	// 99999 or less: use "12345" format
114	// u is value/10, v is last digit
115	c = buf[0] = " 123456789"[u/1000];
116	if (c != ' ') fmt = "0123456789";
117	c = buf[1] = fmt[u/100%10];
118	if (c != ' ') fmt = "0123456789";
119	c = buf[2] = fmt[u/10%10];
120	if (c != ' ') fmt = "0123456789";
121	buf[3] = fmt[u%10];
122	buf[4] = "0123456789"[v];
123	} else {
124	// value has been scaled into 0..9999.9 range
125	// u is value, v is 1/10ths (allows for 92.1M format)
126	if (u >= 100) {
127	// value is >= 100: use "1234M', " 123M" formats
128	c = buf[0] = " 123456789"[u/1000];
129	if (c != ' ') fmt = "0123456789";
130	c = buf[1] = fmt[u/100%10];
131	if (c != ' ') fmt = "0123456789";
132	v = u % 10;
133	u = u / 10;
134	buf[2] = fmt[u%10];
135	} else {
136	// value is < 100: use "92.1M" format
137	c = buf[0] = " 123456789"[u/10];
138	if (c != ' ') fmt = "0123456789";
139	buf[1] = fmt[u%10];
140	buf[2] = '.';
141	}
142	buf[3] = "0123456789"[v];
143	buf[4] = scale[idx]; /* typically scale = " kmgt..." */
144	}
145	}
146
147
148	// Convert unsigned integer to ascii, writing into supplied buffer.
149	// A truncated result contains the first few digits of the result ala strncpy.
150	// Returns a pointer past last generated digit, does _not_ store NUL.
151	void BUG_sizeof_unsigned_not_4(void);
152	char* FAST_FUNC utoa_to_buf(unsigned n, char *buf, unsigned buflen)
153	{
154	unsigned i, out, res;
155	if (sizeof(unsigned) != 4)
156	BUG_sizeof_unsigned_not_4();
157	if (buflen) {
158	out = 0;
159	for (i = 1000000000; i; i /= 10) {
160	res = n / i;
161	if (res \|\| out \|\| i == 1) {
162	if (!--buflen) break;
163	out++;
164	n -= res*i;
165	*buf++ = '0' + res;
166	}
167	}
168	}
169	return buf;
170	}
171
172	/* Convert signed integer to ascii, like utoa_to_buf() */
173	char* FAST_FUNC itoa_to_buf(int n, char *buf, unsigned buflen)
174	{
175	if (buflen && n < 0) {
176	n = -n;
177	*buf++ = '-';
178	buflen--;
179	}
180	return utoa_to_buf((unsigned)n, buf, buflen);
181	}
182
183	// The following two functions use a static buffer, so calling either one a
184	// second time will overwrite previous results.
185	//
186	// The largest 32 bit integer is -2 billion plus null terminator, or 12 bytes.
187	// It so happens that sizeof(int) * 3 is enough for 32+ bits.
188	// (sizeof(int) * 3 + 2 is correct for any width, even 8-bit)
189
190	static char local_buf[sizeof(int) * 3];
191
192	// Convert unsigned integer to ascii using a static buffer (returned).
193	char* FAST_FUNC utoa(unsigned n)
194	{
195	*(utoa_to_buf(n, local_buf, sizeof(local_buf))) = '\0';
196
197	return local_buf;
198	}
199
200	/* Convert signed integer to ascii using a static buffer (returned). */
201	char* FAST_FUNC itoa(int n)
202	{
203	*(itoa_to_buf(n, local_buf, sizeof(local_buf))) = '\0';
204
205	return local_buf;
206	}
207
208	/* Emit a string of hex representation of bytes */
209	char* FAST_FUNC bin2hex(char p, const char cp, int count)
210	{
211	while (count) {
212	unsigned char c = *cp++;
213	/* put lowercase hex digits */
214	*p++ = 0x20 \| bb_hexdigits_upcase[c >> 4];
215	*p++ = 0x20 \| bb_hexdigits_upcase[c & 0xf];
216	count--;
217	}
218	return p;
219	}
220
221	/* Return how long the file at fd is, if there's any way to determine it. */
222	#ifdef UNUSED
223	off_t FAST_FUNC fdlength(int fd)
224	{
225	off_t bottom = 0, top = 0, pos;
226	long size;
227
228	// If the ioctl works for this, return it.
229
230	if (ioctl(fd, BLKGETSIZE, &size) >= 0) return size*512;
231
232	// FIXME: explain why lseek(SEEK_END) is not used here!
233
234	// If not, do a binary search for the last location we can read. (Some
235	// block devices don't do BLKGETSIZE right.)
236
237	do {
238	char temp;
239
240	pos = bottom + (top - bottom) / 2;
241
242	// If we can read from the current location, it's bigger.
243
244	if (lseek(fd, pos, SEEK_SET)>=0 && safe_read(fd, &temp, 1)==1) {
245	if (bottom == top) bottom = top = (top+1) * 2;
246	else bottom = pos;
247
248	// If we can't, it's smaller.
249
250	} else {
251	if (bottom == top) {
252	if (!top) return 0;
253	bottom = top/2;
254	}
255	else top = pos;
256	}
257	} while (bottom + 1 != top);
258
259	return pos + 1;
260	}
261	#endif
262
263	/* It is perfectly ok to pass in a NULL for either width or for
264	* height, in which case that value will not be set. */
265	int FAST_FUNC get_terminal_width_height(int fd, unsigned width, unsigned height)
266	{
267	struct winsize win = { 0, 0, 0, 0 };
268	int ret = ioctl(fd, TIOCGWINSZ, &win);
269
270	if (height) {
271	if (!win.ws_row) {
272	char *s = getenv("LINES");
273	if (s) win.ws_row = atoi(s);
274	}
275	if (win.ws_row <= 1 \|\| win.ws_row >= 30000)
276	win.ws_row = 24;
277	*height = (int) win.ws_row;
278	}
279
280	if (width) {
281	if (!win.ws_col) {
282	char *s = getenv("COLUMNS");
283	if (s) win.ws_col = atoi(s);
284	}
285	if (win.ws_col <= 1 \|\| win.ws_col >= 30000)
286	win.ws_col = 80;
287	*width = (int) win.ws_col;
288	}
289
290	return ret;
291	}
292
293	int FAST_FUNC tcsetattr_stdin_TCSANOW(const struct termios *tp)
294	{
295	return tcsetattr(STDIN_FILENO, TCSANOW, tp);
296	}