X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=libbb%2Fread.c;h=5906bc225dc62dde00025cf77ffde09061acf2a2;hb=86ffe5c15a14dc7f8483faf42ef907c5f861137d;hp=288358d79bfbc9a9bc54692e85d5be0e52188bf0;hpb=0a1446275d88946734417ed96a3c0f1d7ea969e4;p=oweals%2Fbusybox.git

diff --git a/libbb/read.c b/libbb/read.c
index 288358d79..5906bc225 100644
--- a/libbb/read.c
+++ b/libbb/read.c
@@ -4,12 +4,11 @@
  *
  * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
  *
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
-
 #include "libbb.h"
 
-ssize_t safe_read(int fd, void *buf, size_t count)
+ssize_t FAST_FUNC safe_read(int fd, void *buf, size_t count)
 {
 	ssize_t n;
 
@@ -20,65 +19,13 @@ ssize_t safe_read(int fd, void *buf, size_t count)
 	return n;
 }
 
-/* Suppose that you are a shell. You start child processes.
- * They work and eventually exit. You want to get user input.
- * You read stdin. But what happens if last child switched
- * its stdin into O_NONBLOCK mode?
- *
- * *** SURPRISE! It will affect the parent too! ***
- * *** BIG SURPRISE! It stays even after child exits! ***
- *
- * This is a design bug in UNIX API.
- *      fcntl(0, F_SETFL, fcntl(0, F_GETFL, 0) | O_NONBLOCK);
- * will set nonblocking mode not only on _your_ stdin, but
- * also on stdin of your parent, etc.
- *
- * In general,
- *      fd2 = dup(fd1);
- *      fcntl(fd2, F_SETFL, fcntl(fd2, F_GETFL, 0) | O_NONBLOCK);
- * sets both fd1 and fd2 to O_NONBLOCK. This includes cases
- * where duping is done implicitly by fork() etc.
- *
- * We need
- *      fcntl(fd2, F_SETFD, fcntl(fd2, F_GETFD, 0) | O_NONBLOCK);
- * (note SETFD, not SETFL!) but such thing doesn't exist.
- *
- * Alternatively, we need nonblocking_read(fd, ...) which doesn't
- * require O_NONBLOCK dance at all. Actually, it exists:
- *      n = recv(fd, buf, len, MSG_DONTWAIT);
- *      "MSG_DONTWAIT:
- *      Enables non-blocking operation; if the operation
- *      would block, EAGAIN is returned."
- * but recv() works only for sockets!
- *
- * So far I don't see any good solution, I can only propose
- * that affected readers should be careful and use this routine,
- * which detects EAGAIN and uses poll() to wait on the fd.
- * Thankfully, poll() doesn't care about O_NONBLOCK flag.
- */
-ssize_t nonblock_safe_read(int fd, void *buf, size_t count)
-{
-	struct pollfd pfd[1];
-	ssize_t n;
-
-	while (1) {
-		n = safe_read(fd, buf, count);
-		if (n >= 0 || errno != EAGAIN)
-			return n;
-		/* fd is in O_NONBLOCK mode. Wait using poll and repeat */
-		pfd[0].fd = fd;
-		pfd[0].events = POLLIN;
-		safe_poll(pfd, 1, -1);
-	}
-}
-
 /*
  * Read all of the supplied buffer from a file.
  * This does multiple reads as necessary.
  * Returns the amount read, or -1 on an error.
  * A short read is returned on an end of file.
  */
-ssize_t full_read(int fd, void *buf, size_t len)
+ssize_t FAST_FUNC full_read(int fd, void *buf, size_t len)
 {
 	ssize_t cc;
 	ssize_t total;
@@ -106,86 +53,7 @@ ssize_t full_read(int fd, void *buf, size_t len)
 	return total;
 }
 
-// Die with an error message if we can't read the entire buffer.
-void xread(int fd, void *buf, size_t count)
-{
-	if (count) {
-		ssize_t size = full_read(fd, buf, count);
-		if (size != count)
-			bb_error_msg_and_die("short read");
-	}
-}
-
-// Die with an error message if we can't read one character.
-unsigned char xread_char(int fd)
-{
-	char tmp;
-	xread(fd, &tmp, 1);
-	return tmp;
-}
-
-// Read one line a-la fgets. Works only on seekable streams
-char *reads(int fd, char *buffer, size_t size)
-{
-	char *p;
-
-	if (size < 2)
-		return NULL;
-	size = full_read(fd, buffer, size-1);
-	if ((ssize_t)size <= 0)
-		return NULL;
-
-	buffer[size] = '\0';
-	p = strchr(buffer, '\n');
-	if (p) {
-		off_t offset;
-		*p++ = '\0';
-		// avoid incorrect (unsigned) widening
-		offset = (off_t)(p - buffer) - (off_t)size;
-		// set fd position right after '\n'
-		if (offset && lseek(fd, offset, SEEK_CUR) == (off_t)-1)
-			return NULL;
-	}
-	return buffer;
-}
-
-// Reads one line a-la fgets (but doesn't save terminating '\n').
-// Reads byte-by-byte. Useful when it is important to not read ahead.
-// Bytes are appended to pfx (which must be malloced, or NULL).
-char *xmalloc_reads(int fd, char *buf, size_t *maxsz_p)
-{
-	char *p;
-	size_t sz = buf ? strlen(buf) : 0;
-	size_t maxsz = maxsz_p ? *maxsz_p : MAXINT(size_t);
-
-	goto jump_in;
-	while (sz < maxsz) {
-		if (p - buf == sz) {
- jump_in:
-			buf = xrealloc(buf, sz + 128);
-			p = buf + sz;
-			sz += 128;
-		}
-		/* nonblock_safe_read() because we are used by e.g. shells */
-		if (nonblock_safe_read(fd, p, 1) != 1) { /* EOF/error */
-			if (p == buf) { /* we read nothing */
-				free(buf);
-				return NULL;
-			}
-			break;
-		}
-		if (*p == '\n')
-			break;
-		p++;
-	}
-	*p = '\0';
-	if (maxsz_p)
-		*maxsz_p  = p - buf;
-	p++;
-	return xrealloc(buf, p - buf);
-}
-
-ssize_t read_close(int fd, void *buf, size_t size)
+ssize_t FAST_FUNC read_close(int fd, void *buf, size_t size)
 {
 	/*int e;*/
 	size = full_read(fd, buf, size);
@@ -195,99 +63,10 @@ ssize_t read_close(int fd, void *buf, size_t size)
 	return size;
 }
 
-ssize_t open_read_close(const char *filename, void *buf, size_t size)
+ssize_t FAST_FUNC open_read_close(const char *filename, void *buf, size_t size)
 {
 	int fd = open(filename, O_RDONLY);
 	if (fd < 0)
 		return fd;
 	return read_close(fd, buf, size);
 }
-
-// Read (potentially big) files in one go. File size is estimated by
-// lseek to end.
-void *xmalloc_open_read_close(const char *filename, size_t *sizep)
-{
-	char *buf;
-	size_t size;
-	int fd;
-	off_t len;
-	struct stat st;
-
-	fd = open(filename, O_RDONLY);
-	if (fd < 0)
-		return NULL;
-
-	st.st_size = 0; /* in case fstat fail, define to 0 */
-	fstat(fd, &st);
-	/* /proc/N/stat files report len 0 here */
-	/* In order to make such files readable, we add small const */
-	len = st.st_size | 0x3ff; /* read only 1k on unseekable files */
-	size = sizep ? *sizep : INT_MAX;
-	if (len < size)
-		size = len;
-	buf = xmalloc(size + 1);
-	size = read_close(fd, buf, size);
-	if ((ssize_t)size < 0) {
-		free(buf);
-		return NULL;
-	}
-	xrealloc(buf, size + 1);
-	buf[size] = '\0';
-
-	if (sizep)
-		*sizep = size;
-	return buf;
-}
-
-#ifdef USING_LSEEK_TO_GET_SIZE
-/* Alternatively, file size can be obtained by lseek to the end.
- * The code is slightly bigger. Retained in case fstat approach
- * will not work for some weird cases (/proc, block devices, etc).
- * (NB: lseek also can fail to work for some weird files) */
-
-// Read (potentially big) files in one go. File size is estimated by
-// lseek to end.
-void *xmalloc_open_read_close(const char *filename, size_t *sizep)
-{
-	char *buf;
-	size_t size;
-	int fd;
-	off_t len;
-
-	fd = open(filename, O_RDONLY);
-	if (fd < 0)
-		return NULL;
-
-	/* /proc/N/stat files report len 0 here */
-	/* In order to make such files readable, we add small const */
-	size = 0x3ff; /* read only 1k on unseekable files */
-	len = lseek(fd, 0, SEEK_END) | 0x3ff; /* + up to 1k */
-	if (len != (off_t)-1) {
-		xlseek(fd, 0, SEEK_SET);
-		size = sizep ? *sizep : INT_MAX;
-		if (len < size)
-			size = len;
-	}
-
-	buf = xmalloc(size + 1);
-	size = read_close(fd, buf, size);
-	if ((ssize_t)size < 0) {
-		free(buf);
-		return NULL;
-	}
-	xrealloc(buf, size + 1);
-	buf[size] = '\0';
-
-	if (sizep)
-		*sizep = size;
-	return buf;
-}
-#endif
-
-void *xmalloc_xopen_read_close(const char *filename, size_t *sizep)
-{
-	void *buf = xmalloc_open_read_close(filename, sizep);
-	if (!buf)
-		bb_perror_msg_and_die("can't read '%s'", filename);
-	return buf;
-}