X-Git-Url: http://git.tuebingen.mpg.de/?p=adu.git;a=blobdiff_plain;f=fd.c;h=902e8f1898d29c7ace5a481c4f731ce7134f4433;hp=cfef4d9a663268d24c130ecf11fee71fac0864a9;hb=4884395952589ec5310ad6220928d4bd25ab10cb;hpb=a4cf08e8062d1d73c343a628563acf4d9f454742

diff --git a/fd.c b/fd.c
index cfef4d9..902e8f1 100644
--- a/fd.c
+++ b/fd.c
@@ -1,208 +1,73 @@
 /*
- * Copyright (C) 2006-2008 Andre Noll <maan@systemlinux.org>
+ * Copyright (C) 2006-2008 Andre Noll <maan@tuebingen.mpg.de>
  *
  * Licensed under the GPL v2. For licencing details see COPYING.
  */
 
-/** \file fd.c Helper functions for file descriptor handling. */
+/** \file fd.c \brief Helper functions for file descriptor handling. */
 
 #include <sys/types.h>
 #include <dirent.h>
 #include <sys/mman.h>
-#include <fcntl.h>
-#include <sys/select.h>
+#include <string.h>
 
 #include "adu.h"
 #include "error.h"
+#include "string.h"
+#include "fd.h"
 
 /**
- * Write a buffer to a file descriptor, re-write on short writes.
+ * Wrapper for the write system call.
  *
- * \param fd The file descriptor.
- * \param buf The buffer to be sent.
- * \param len The length of \a buf.
+ * \param fd The file descriptor to write to.
+ * \param buf The buffer to write.
+ * \param size The length of \a buf in bytes.
  *
- * \return Standard. In any case, the number of bytes that have been written is
- * stored in \a len.
- */
-int write_all(int fd, const char *buf, size_t *len)
-{
-	size_t total = *len;
-
-	assert(total);
-	*len = 0;
-	while (*len < total) {
-		int ret = write(fd, buf + *len, total - *len);
-		if (ret == -1)
-			return -ERRNO_TO_ERROR(errno);
-		*len += ret;
-	}
-	return 1;
-}
-
-/**
- * Check whether a file exists.
- *
- * \param fn The file name.
- *
- * \return Non-zero iff file exists.
- */
-int file_exists(const char *fn)
-{
-	struct stat statbuf;
-
-	return !stat(fn, &statbuf);
-}
-
-/**
- * Paraslash's wrapper for select(2).
- *
- * It calls select(2) (with no exceptfds) and starts over if select() was
- * interrupted by a signal.
- *
- * \param n The highest-numbered descriptor in any of the two sets, plus 1.
- * \param readfds fds that should be checked for readability.
- * \param writefds fds that should be checked for writablility.
- * \param timeout_tv upper bound on the amount of time elapsed before select()
- * returns.
- *
- * \return The return value of the underlying select() call on success, the
- * negative system error code on errors.
- *
- * All arguments are passed verbatim to select(2).
- * \sa select(2) select_tut(2).
- */
-int para_select(int n, fd_set *readfds, fd_set *writefds,
-		struct timeval *timeout_tv)
-{
-	int ret, err;
-	do {
-		ret = select(n, readfds, writefds, NULL, timeout_tv);
-		err = errno;
-	} while (ret < 0 && err == EINTR);
-	if (ret < 0)
-		return -ERRNO_TO_ERROR(errno);
-	return ret;
-}
-
-/**
- * Set a file descriptor to blocking mode.
- *
- * \param fd The file descriptor.
+ * This function writes out the given buffer and retries if an interrupt
+ * occurred during the write. The file descriptor is assumed to be in blocking
+ * mode (i.e., EAGAIN is treated as an error).
  *
  * \return Standard.
- */
-__must_check int mark_fd_blocking(int fd)
-{
-	int flags = fcntl(fd, F_GETFL);
-	if (flags < 0)
-		return -ERRNO_TO_ERROR(errno);
-	flags = fcntl(fd, F_SETFL, ((long)flags) & ~O_NONBLOCK);
-	if (flags < 0)
-		return -ERRNO_TO_ERROR(errno);
-	return 1;
-}
-
-/**
- * Set a file descriptor to non-blocking mode.
  *
- * \param fd The file descriptor.
- *
- * \return Standard.
+ * \sa write(2).
  */
-__must_check int mark_fd_nonblocking(int fd)
-{
-	int flags = fcntl(fd, F_GETFL);
-	if (flags < 0)
-		return -ERRNO_TO_ERROR(errno);
-	flags = fcntl(fd, F_SETFL, ((long)flags) | O_NONBLOCK);
-	if (flags < 0)
-		return -ERRNO_TO_ERROR(errno);
-	return 1;
-}
-
-/**
- * Set a file descriptor in a fd_set.
- *
- * \param fd The file descriptor to be set.
- * \param fds The file descriptor set.
- * \param max_fileno Highest-numbered file descriptor.
- *
- * This wrapper for FD_SET() passes its first two arguments to \p FD_SET. Upon
- * return, \a max_fileno contains the maximum of the old_value and \a fd.
- *
- * \sa para_select.
-*/
-void para_fd_set(int fd, fd_set *fds, int *max_fileno)
+static ssize_t __write(int fd, const void *buf, size_t size)
 {
+	ssize_t ret;
 
-	if (fd < 0 || fd >= FD_SETSIZE) {
-		EMERG_LOG("fatal: tried to add invalid fd %d\n", fd);
-		exit(EXIT_FAILURE);
+	for (;;) {
+		ret = write(fd, buf, size);
+		if (ret < 0 && errno == EINTR)
+			continue;
+		return ret >= 0? ret : -ERRNO_TO_ERROR(errno);
 	}
-#if 0
-	{
-		int flags = fcntl(fd, F_GETFL);
-		if (!(flags & O_NONBLOCK)) {
-			EMERG_LOG("fd %d is a blocking file descriptor\n", fd);
-			exit(EXIT_FAILURE);
-		}
-	}
-#endif
-	FD_SET(fd, fds);
-	*max_fileno = MAX(*max_fileno, fd);
 }
 
 /**
- * Paraslash's wrapper for fgets(3).
- *
- * \param line Pointer to the buffer to store the line.
- * \param size The size of the buffer given by \a line.
- * \param f The stream to read from.
+ * Write the whole buffer to a file descriptor.
  *
- * \return Unlike the standard fgets() function, an integer value
- * is returned. On success, this function returns 1. On errors, -E_FGETS
- * is returned. A zero return value indicates an end of file condition.
- */
-__must_check int para_fgets(char *line, int size, FILE *f)
-{
-again:
-	if (fgets(line, size, f))
-		return 1;
-	if (feof(f))
-		return 0;
-	if (!ferror(f))
-		return -E_FGETS;
-	if (errno != EINTR) {
-		ERROR_LOG("%s\n", strerror(errno));
-		return -E_FGETS;
-	}
-	clearerr(f);
-	goto again;
-}
-
-/**
- * Paraslash's wrapper for mmap.
+ * \param fd The file descriptor to write to.
+ * \param buf The buffer to write.
+ * \param size The length of \a buf in bytes.
  *
- * \param length Number of bytes to mmap.
- * \param prot Either PROT_NONE or the bitwise OR of one or more of
- * PROT_EXEC PROT_READ PROT_WRITE.
- * \param flags Exactly one of MAP_SHARED and MAP_PRIVATE.
- * \param fd The file to mmap from.
- * \param offset Mmap start.
+ * This function writes the given buffer and continues on short writes and
+ * when interrupted by a signal.
  *
- * \return This function either returns a valid pointer to the mapped area
- * or calls exit() on errors.
+ * \return Standard.
  */
-void *para_mmap(size_t length, int prot, int flags, int fd, off_t offset)
+static ssize_t write_all(int fd, const void *buf, size_t size)
 {
-	void *ret = mmap(NULL, length, prot, flags, fd, offset);
-	if (ret != MAP_FAILED)
-		return ret;
-	EMERG_LOG("mmap failed: %s\n", strerror(errno));
-	EMERG_LOG("length: %zu, flags: %d, fd: %d, offset: %zu\n",
-		length, flags, fd, (size_t)offset);
-	exit(EXIT_FAILURE);
+//	DEBUG_LOG("writing %zu bytes\n", size);
+	const char *b = buf;
+	while (size) {
+		ssize_t ret = __write(fd, b, size);
+//		DEBUG_LOG("ret: %zd\n", ret);
+		if (ret < 0)
+			return ret;
+		b += ret;
+		size -= ret;
+	}
+	return 1;
 }
 
 /**
@@ -219,7 +84,7 @@ void *para_mmap(size_t length, int prot, int flags, int fd, off_t offset)
  *
  * \sa open(2).
  */
-int para_open(const char *path, int flags, mode_t mode)
+static int __open(const char *path, int flags, mode_t mode)
 {
 	int ret = open(path, flags, mode);
 
@@ -228,6 +93,32 @@ int para_open(const char *path, int flags, mode_t mode)
 	return -ERRNO_TO_ERROR(errno);
 }
 
+/**
+ * Open a file, write the given buffer and close the file.
+ *
+ * \param filename Full path to the file to open.
+ * \param buf The buffer to write to the file.
+ * \param size The size of \a buf.
+ *
+ * \return Standard.
+ */
+int adu_write_file(const char *filename, const void *buf, size_t size)
+{
+	int ret, fd;
+
+	ret = __open(filename, O_WRONLY | O_CREAT | O_EXCL, 0644);
+	if (ret < 0)
+		return ret;
+	fd = ret;
+	ret = write_all(fd, buf, size);
+	if (ret < 0)
+		goto out;
+	ret = 1;
+out:
+	close(fd);
+	return ret;
+}
+
 /**
  * Wrapper for chdir(2).
  *
@@ -235,7 +126,7 @@ int para_open(const char *path, int flags, mode_t mode)
  *
  * \return Standard.
  */
-int para_chdir(const char *path)
+static int __chdir(const char *path)
 {
 	int ret = chdir(path);
 
@@ -268,17 +159,17 @@ int para_chdir(const char *path)
  * \sa getcwd(3).
  *
  */
-int para_opendir(const char *dirname, DIR **dir, int *cwd)
+int adu_opendir(const char *dirname, DIR **dir, int *cwd)
 {
 	int ret;
 
 	if (cwd) {
-		ret = para_open(".", O_RDONLY, 0);
+		ret = __open(".", O_RDONLY, 0);
 		if (ret < 0)
 			return ret;
 		*cwd = ret;
 	}
-	ret = para_chdir(dirname);
+	ret = __chdir(dirname);
 	if (ret < 0)
 		goto close_cwd;
 	*dir = opendir(".");
@@ -301,7 +192,7 @@ close_cwd:
  *
  * \return Standard.
  */
-int para_fchdir(int fd)
+int adu_fchdir(int fd)
 {
 	if (fchdir(fd) < 0)
 		return -ERRNO_TO_ERROR(errno);
@@ -309,51 +200,25 @@ int para_fchdir(int fd)
 }
 
 /**
- * A wrapper for mkdir(2).
- *
- * \param path Name of the directory to create.
- * \param mode The permissions to use.
- *
- * \return Standard.
- */
-int para_mkdir(const char *path, mode_t mode)
-{
-	if (!mkdir(path, mode))
-		return 1;
-	return -ERRNO_TO_ERROR(errno);
-}
-
-/**
- * Open a file and map it into memory.
+ * Open a file read-only and map it into memory.
  *
  * \param path Name of the regular file to map.
- * \param open_mode Either \p O_RDONLY or \p O_RDWR.
  * \param map On success, the mapping is returned here.
- * \param size size of the mapping.
- * \param fd_ptr The file descriptor of the mapping.
+ * \param size Result parameter: size of the mapping in bytes.
  *
- * If \a fd_ptr is \p NULL, the file descriptor resulting from the underlying
- * open call is closed after mmap().  Otherwise the file is kept open and the
- * file descriptor is returned in \a fd_ptr.
+ * The file will be mapped privately with memory protection PROT_READ. The file
+ * descriptor resulting from the underlying open call is closed after mmap().
  *
  * \return Standard.
  *
- * \sa para_open(), mmap(2).
+ * \sa mmap(2).
  */
-int mmap_full_file(const char *path, int open_mode, void **map,
-		size_t *size, int *fd_ptr)
+int mmap_file_ro(const char *path, void **map, size_t *size)
 {
-	int fd, ret, mmap_prot, mmap_flags;
+	int fd, ret;
 	struct stat file_status;
 
-	if (open_mode == O_RDONLY) {
-		mmap_prot = PROT_READ;
-		mmap_flags = MAP_PRIVATE;
-	} else {
-		mmap_prot = PROT_READ | PROT_WRITE;
-		mmap_flags = MAP_SHARED;
-	}
-	ret = para_open(path, open_mode, 0);
+	ret = __open(path, O_RDONLY, 0);
 	if (ret < 0)
 		return ret;
 	fd = ret;
@@ -366,7 +231,7 @@ int mmap_full_file(const char *path, int open_mode, void **map,
 	DEBUG_LOG("%s: size %zu\n", path, *size);
 	if (!*size)
 		goto out;
-	*map = mmap(NULL, *size, mmap_prot, mmap_flags, fd, 0);
+	*map = mmap(NULL, *size, PROT_READ, MAP_PRIVATE, fd, 0);
 	if (*map == MAP_FAILED) {
 		*map = NULL;
 		ret = -E_MMAP;
@@ -374,10 +239,7 @@ int mmap_full_file(const char *path, int open_mode, void **map,
 	}
 	ret = 1;
 out:
-	if (ret < 0 || !fd_ptr)
-		close(fd);
-	else
-		*fd_ptr = fd;
+	close(fd);
 	return ret;
 }
 
@@ -391,7 +253,7 @@ out:
  *
  * \sa munmap(2), mmap_full_file().
  */
-int para_munmap(void *start, size_t length)
+int adu_munmap(void *start, size_t length)
 {
 	int err;
 	if (munmap(start, length) >= 0)
@@ -402,27 +264,53 @@ int para_munmap(void *start, size_t length)
 	return -ERRNO_TO_ERROR(err);
 }
 
+__must_check __malloc static char *adu_dirname(const char *name)
+{
+	char *p, *ret;
+
+	if (!name || !*name)
+		return NULL;
+	ret = adu_strdup(name);
+	p = strrchr(ret, '/');
+	if (!p)
+		*ret = '\0';
+	else
+		*p = '\0';
+	return ret;
+}
+
 /**
- * Check a file descriptor for writability.
+ * Recursive mkdir
+ *
+ * \param p Full path that should be created.
  *
- * \param fd The file descriptor.
+ * \param mode Use this mode when creating directories.
  *
- * \return positive if fd is ready for writing, zero if it isn't, negative if
- * an error occurred.
+ * \return 0 if successful, -E_MKDIR on errors.
  */
-
-int write_ok(int fd)
+int mkpath(const char *p, mode_t mode)
 {
-	struct timeval tv = {0, 0};
-	fd_set wfds;
-	int ret;
-again:
-	FD_ZERO(&wfds);
-	FD_SET(fd, &wfds);
-	tv.tv_sec = 0;
-	tv.tv_usec = 0;
-	ret = select(fd + 1, NULL, &wfds, NULL, &tv);
-	if (ret < 0 && errno == EINTR)
-		goto again;
+	char *parent, *path;
+	int ret = -E_MKDIR;
+
+	DEBUG_LOG("%s\n", p);
+	if (strcmp(p, ".") == 0 || strcmp(p, "/") == 0 || strcmp(p, "") == 0) {
+		DEBUG_LOG("reached beginning of path\n");
+		return 0;
+	}
+	path = adu_strdup(p);
+	parent = adu_dirname(p);
+	if (!parent)
+		goto out;
+	ret = mkpath(parent, mode);
+	if (ret < 0)
+		goto out;
+	INFO_LOG("making dir %s\n", path);
+	ret = 0;
+	if ((mkdir(path, mode) == -1) && (errno != EEXIST))
+		ret = -E_MKDIR;
+out:
+	free(parent);
+	free(path);
 	return ret;
 }