/*
- * util.c
+ * util.c - utility functions
*/
/*
- * Copyright (C) 2012, 2013 Eric Biggers
+ * Copyright 2012-2023 Eric Biggers
*
- * This file is part of wimlib, a library for working with WIM files.
+ * This file is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU Lesser General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or (at your option) any
+ * later version.
*
- * wimlib is free software; you can redistribute it and/or modify it under the
- * terms of the GNU General Public License as published by the Free
- * Software Foundation; either version 3 of the License, or (at your option)
- * any later version.
- *
- * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY
- * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
- * A PARTICULAR PURPOSE. See the GNU General Public License for more
+ * This file is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
* details.
*
- * You should have received a copy of the GNU General Public License
- * along with wimlib; if not, see http://www.gnu.org/licenses/.
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this file; if not, see https://www.gnu.org/licenses/.
*/
-#include "config.h"
-
-
-#undef _GNU_SOURCE
-/* Make sure the POSIX-compatible strerror_r() is declared, rather than the GNU
- * version, which has a different return type. */
-#include <string.h>
-
-#define _GNU_SOURCE
-
-#include "endianness.h"
-#include "timestamp.h"
-#include "wimlib_internal.h"
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
-#include <ctype.h>
#include <errno.h>
-#include <stdarg.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <stdio.h>
#include <stdlib.h>
+#include <string.h>
+#ifdef HAVE_SYS_SYSCTL_H
+# include <sys/types.h>
+# include <sys/sysctl.h>
+#endif
+#ifdef HAVE_SYS_SYSCALL_H
+# include <sys/syscall.h>
+#endif
#include <unistd.h>
+#include "wimlib.h"
+#include "wimlib/assert.h"
+#include "wimlib/error.h"
+#include "wimlib/timestamp.h"
+#include "wimlib/util.h"
-#ifdef __WIN32__
-# include "win32.h"
-# define pread win32_pread
-# define pwrite win32_pwrite
-# define writev win32_writev
-#else
-# include <sys/uio.h> /* for writev() and `struct iovec' */
-#endif
+/*******************
+ * Memory allocation
+ *******************/
-static size_t
-utf16le_strlen(const utf16lechar *s)
-{
- const utf16lechar *p = s;
- while (*p)
- p++;
- return (p - s) * sizeof(utf16lechar);
-}
+static void *(*wimlib_malloc_func) (size_t) = malloc;
+static void (*wimlib_free_func) (void *) = free;
+static void *(*wimlib_realloc_func)(void *, size_t) = realloc;
-#ifdef __WIN32__
-# define wimlib_vfprintf vfwprintf
-#else
-/* Handle %W for UTF16-LE printing.
- *
- * TODO: this is not yet done properly--- it's assumed that if the format string
- * contains %W, then it contains no other format specifiers.
- */
-static int
-wimlib_vfprintf(FILE *fp, const tchar *format, va_list va)
+void *
+wimlib_malloc(size_t size)
{
- const tchar *p;
- int n;
-
- for (p = format; *p; p++)
- if (*p == T('%') && *(p + 1) == T('W'))
- goto special;
- return tvfprintf(fp, format, va);
-special:
- n = 0;
- for (p = format; *p; p++) {
- if (*p == T('%') && (*(p + 1) == T('W'))) {
- int ret;
- tchar *tstr;
- size_t tstr_nbytes;
- utf16lechar *ucs = va_arg(va, utf16lechar*);
-
- if (ucs) {
- size_t ucs_nbytes = utf16le_strlen(ucs);
-
- ret = utf16le_to_tstr(ucs, ucs_nbytes,
- &tstr, &tstr_nbytes);
- if (ret) {
- ret = tfprintf(fp, T("??????"));
- } else {
- ret = tfprintf(fp, T("%"TS), tstr);
- FREE(tstr);
- }
- if (ret < 0)
- return -1;
- else
- n += ret;
- } else {
- n += tfprintf(fp, T("(null)"));
- }
- p++;
- } else {
- if (tputc(*p, fp) == EOF)
- return -1;
- n++;
+ void *ptr;
+
+retry:
+ ptr = (*wimlib_malloc_func)(size);
+ if (unlikely(!ptr)) {
+ if (size == 0) {
+ size = 1;
+ goto retry;
}
}
- return n;
+ return ptr;
}
-int
-wimlib_printf(const tchar *format, ...)
-{
- int ret;
- va_list va;
-
- va_start(va, format);
- ret = wimlib_vfprintf(stdout, format, va);
- va_end(va);
- return ret;
-}
-
-int
-wimlib_fprintf(FILE *fp, const tchar *format, ...)
+void
+wimlib_free_memory(void *ptr)
{
- int ret;
- va_list va;
-
- va_start(va, format);
- ret = wimlib_vfprintf(fp, format, va);
- va_end(va);
- return ret;
+ (*wimlib_free_func)(ptr);
}
-#endif
-#if defined(ENABLE_ERROR_MESSAGES) || defined(ENABLE_DEBUG)
-static void
-wimlib_vmsg(const tchar *tag, const tchar *format,
- va_list va, bool perror)
+void *
+wimlib_realloc(void *ptr, size_t size)
{
-#ifndef DEBUG
- if (wimlib_print_errors) {
-#endif
- int errno_save = errno;
- fflush(stdout);
- tfputs(tag, stderr);
- wimlib_vfprintf(stderr, format, va);
- if (perror && errno_save != 0) {
- tchar buf[50];
- int res;
- res = tstrerror_r(errno_save, buf, sizeof(buf));
- if (res) {
- tsprintf(buf,
- T("unknown error (errno=%d)"),
- errno_save);
- }
- tfprintf(stderr, T(": %"TS), buf);
- }
- tputc(T('\n'), stderr);
- fflush(stderr);
- errno = errno_save;
-#ifndef DEBUG
- }
-#endif
+ if (size == 0)
+ size = 1;
+ return (*wimlib_realloc_func)(ptr, size);
}
-#endif
-
-/* True if wimlib is to print an informational message when an error occurs.
- * This can be turned off by calling wimlib_set_print_errors(false). */
-#ifdef ENABLE_ERROR_MESSAGES
-static bool wimlib_print_errors = false;
-
-void
-wimlib_error(const tchar *format, ...)
+void *
+wimlib_calloc(size_t nmemb, size_t size)
{
- va_list va;
-
- va_start(va, format);
- wimlib_vmsg(T("\r[ERROR] "), format, va, false);
- va_end(va);
-}
+ size_t total_size = nmemb * size;
+ void *p;
-void
-wimlib_error_with_errno(const tchar *format, ...)
-{
- va_list va;
+ if (size != 0 && nmemb > SIZE_MAX / size) {
+ errno = ENOMEM;
+ return NULL;
+ }
- va_start(va, format);
- wimlib_vmsg(T("\r[ERROR] "), format, va, true);
- va_end(va);
+ p = MALLOC(total_size);
+ if (p)
+ p = memset(p, 0, total_size);
+ return p;
}
-void
-wimlib_warning(const tchar *format, ...)
+char *
+wimlib_strdup(const char *str)
{
- va_list va;
-
- va_start(va, format);
- wimlib_vmsg(T("\r[WARNING] "), format, va, false);
- va_end(va);
+ return memdup(str, strlen(str) + 1);
}
-void
-wimlib_warning_with_errno(const tchar *format, ...)
+#ifdef _WIN32
+wchar_t *
+wimlib_wcsdup(const wchar_t *str)
{
- va_list va;
-
- va_start(va, format);
- wimlib_vmsg(T("\r[WARNING] "), format, va, true);
- va_end(va);
+ return memdup(str, (wcslen(str) + 1) * sizeof(wchar_t));
}
-
#endif
-#if defined(ENABLE_DEBUG) || defined(ENABLE_MORE_DEBUG)
-void wimlib_debug(const tchar *file, int line, const char *func,
- const tchar *format, ...)
+void *
+wimlib_aligned_malloc(size_t size, size_t alignment)
{
- va_list va;
- tchar buf[tstrlen(file) + strlen(func) + 30];
-
- tsprintf(buf, T("[%"TS" %d] %s(): "), file, line, func);
+ wimlib_assert(is_power_of_2(alignment));
- va_start(va, format);
- wimlib_vmsg(buf, format, va, false);
- va_end(va);
-}
-#endif
-
-WIMLIBAPI int
-wimlib_set_print_errors(bool show_error_messages)
-{
-#ifdef ENABLE_ERROR_MESSAGES
- wimlib_print_errors = show_error_messages;
- return 0;
-#else
- if (show_error_messages)
- return WIMLIB_ERR_UNSUPPORTED;
- else
- return 0;
-#endif
+ void *ptr = MALLOC(sizeof(void *) + alignment - 1 + size);
+ if (ptr) {
+ void *orig_ptr = ptr;
+ ptr = (void *)ALIGN((uintptr_t)ptr + sizeof(void *), alignment);
+ ((void **)ptr)[-1] = orig_ptr;
+ }
+ return ptr;
}
-static const tchar *error_strings[] = {
- [WIMLIB_ERR_SUCCESS]
- = T("Success"),
- [WIMLIB_ERR_ALREADY_LOCKED]
- = T("The WIM is already locked for writing"),
- [WIMLIB_ERR_COMPRESSED_LOOKUP_TABLE]
- = T("Lookup table is compressed"),
- [WIMLIB_ERR_DECOMPRESSION]
- = T("Failed to decompress compressed data"),
- [WIMLIB_ERR_DELETE_STAGING_DIR]
- = T("Failed to delete staging directory"),
- [WIMLIB_ERR_FILESYSTEM_DAEMON_CRASHED]
- = T("The process servicing the mounted WIM has crashed"),
- [WIMLIB_ERR_FORK]
- = T("Failed to fork another process"),
- [WIMLIB_ERR_FUSE]
- = T("An error was returned by fuse_main()"),
- [WIMLIB_ERR_FUSERMOUNT]
- = T("Could not execute the `fusermount' program, or it exited "
- "with a failure status"),
- [WIMLIB_ERR_ICONV_NOT_AVAILABLE]
- = T("The iconv() function does not seem to work. "
- "Maybe check to make sure the directory /usr/lib/gconv exists"),
- [WIMLIB_ERR_IMAGE_COUNT]
- = T("Inconsistent image count among the metadata "
- "resources, the WIM header, and/or the XML data"),
- [WIMLIB_ERR_INSUFFICIENT_PRIVILEGES_TO_EXTRACT]
- = T("User does not have sufficient privileges to correctly extract the data"),
- [WIMLIB_ERR_IMAGE_NAME_COLLISION]
- = T("Tried to add an image with a name that is already in use"),
- [WIMLIB_ERR_INTEGRITY]
- = T("The WIM failed an integrity check"),
- [WIMLIB_ERR_INVALID_CAPTURE_CONFIG]
- = T("The capture configuration string was invalid"),
- [WIMLIB_ERR_INVALID_CHUNK_SIZE]
- = T("The WIM is compressed but does not have a chunk "
- "size of 32768"),
- [WIMLIB_ERR_INVALID_COMPRESSION_TYPE]
- = T("The WIM is compressed, but is not marked as having LZX or "
- "XPRESS compression"),
- [WIMLIB_ERR_INVALID_DENTRY]
- = T("A directory entry in the WIM was invalid"),
- [WIMLIB_ERR_INVALID_HEADER_SIZE]
- = T("The WIM header was not 208 bytes"),
- [WIMLIB_ERR_INVALID_IMAGE]
- = T("Tried to select an image that does not exist in the WIM"),
- [WIMLIB_ERR_INVALID_INTEGRITY_TABLE]
- = T("The WIM's integrity table is invalid"),
- [WIMLIB_ERR_INVALID_LOOKUP_TABLE_ENTRY]
- = T("An entry in the WIM's lookup table is invalid"),
- [WIMLIB_ERR_INVALID_MULTIBYTE_STRING]
- = T("A string was not valid in the current locale's character encoding"),
- [WIMLIB_ERR_INVALID_OVERLAY]
- = T("Conflicting files in overlay when creating a WIM image"),
- [WIMLIB_ERR_INVALID_PARAM]
- = T("An invalid parameter was given"),
- [WIMLIB_ERR_INVALID_PART_NUMBER]
- = T("The part number or total parts of the WIM is invalid"),
- [WIMLIB_ERR_INVALID_REPARSE_DATA]
- = T("The reparse data of a reparse point was invalid"),
- [WIMLIB_ERR_INVALID_RESOURCE_HASH]
- = T("The SHA1 message digest of a WIM resource did not match the expected value"),
- [WIMLIB_ERR_INVALID_RESOURCE_SIZE]
- = T("A resource entry in the WIM has an invalid size"),
- [WIMLIB_ERR_INVALID_SECURITY_DATA]
- = T("The table of security descriptors in the WIM is invalid"),
- [WIMLIB_ERR_INVALID_UNMOUNT_MESSAGE]
- = T("The version of wimlib that has mounted a WIM image is incompatible with the "
- "version being used to unmount it"),
- [WIMLIB_ERR_INVALID_UTF8_STRING]
- = T("A string provided as input by the user was not a valid UTF-8 string"),
- [WIMLIB_ERR_INVALID_UTF16_STRING]
- = T("A string in a WIM dentry is not a valid UTF-16LE string"),
- [WIMLIB_ERR_LIBXML_UTF16_HANDLER_NOT_AVAILABLE]
- = T("libxml2 was unable to find a character encoding conversion handler "
- "for UTF-16LE"),
- [WIMLIB_ERR_LINK]
- = T("Failed to create a hard or symbolic link when extracting "
- "a file from the WIM"),
- [WIMLIB_ERR_MKDIR]
- = T("Failed to create a directory"),
- [WIMLIB_ERR_MQUEUE]
- = T("Failed to create or use a POSIX message queue"),
- [WIMLIB_ERR_NOMEM]
- = T("Ran out of memory"),
- [WIMLIB_ERR_NOTDIR]
- = T("Expected a directory"),
- [WIMLIB_ERR_NOT_A_WIM_FILE]
- = T("The file did not begin with the magic characters that "
- "identify a WIM file"),
- [WIMLIB_ERR_NO_FILENAME]
- = T("The WIM is not identified with a filename"),
- [WIMLIB_ERR_NTFS_3G]
- = T("NTFS-3g encountered an error (check errno)"),
- [WIMLIB_ERR_OPEN]
- = T("Failed to open a file"),
- [WIMLIB_ERR_OPENDIR]
- = T("Failed to open a directory"),
- [WIMLIB_ERR_READ]
- = T("Could not read data from a file"),
- [WIMLIB_ERR_READLINK]
- = T("Could not read the target of a symbolic link"),
- [WIMLIB_ERR_RENAME]
- = T("Could not rename a file"),
- [WIMLIB_ERR_REPARSE_POINT_FIXUP_FAILED]
- = T("Unable to complete reparse point fixup"),
- [WIMLIB_ERR_RESOURCE_ORDER]
- = T("The components of the WIM were arranged in an unexpected order"),
- [WIMLIB_ERR_SPECIAL_FILE]
- = T("Encountered a special file that cannot be archived"),
- [WIMLIB_ERR_SPLIT_INVALID]
- = T("The WIM is part of an invalid split WIM"),
- [WIMLIB_ERR_SPLIT_UNSUPPORTED]
- = T("The WIM is part of a split WIM, which is not supported for this operation"),
- [WIMLIB_ERR_STAT]
- = T("Could not read the metadata for a file or directory"),
- [WIMLIB_ERR_TIMEOUT]
- = T("Timed out while waiting for a message to arrive from another process"),
- [WIMLIB_ERR_UNICODE_STRING_NOT_REPRESENTABLE]
- = T("A Unicode string could not be represented in the current locale's encoding"),
- [WIMLIB_ERR_UNKNOWN_VERSION]
- = T("The WIM file is marked with an unknown version number"),
- [WIMLIB_ERR_UNSUPPORTED]
- = T("The requested operation is unsupported"),
- [WIMLIB_ERR_VOLUME_LACKS_FEATURES]
- = T("The volume did not support a feature necessary to complete the operation"),
- [WIMLIB_ERR_WRITE]
- = T("Failed to write data to a file"),
- [WIMLIB_ERR_XML]
- = T("The XML data of the WIM is invalid"),
-};
-
-WIMLIBAPI const tchar *
-wimlib_get_error_string(enum wimlib_error_code code)
+void
+wimlib_aligned_free(void *ptr)
{
- if (code < 0 || code >= ARRAY_LEN(error_strings))
- return NULL;
- else
- return error_strings[code];
+ if (ptr)
+ FREE(((void **)ptr)[-1]);
}
-
-
-#ifdef ENABLE_CUSTOM_MEMORY_ALLOCATOR
-void *(*wimlib_malloc_func) (size_t) = malloc;
-void (*wimlib_free_func) (void *) = free;
-void *(*wimlib_realloc_func)(void *, size_t) = realloc;
-
void *
-wimlib_calloc(size_t nmemb, size_t size)
-{
- size_t total_size = nmemb * size;
- void *p = MALLOC(total_size);
- if (p)
- memset(p, 0, total_size);
- return p;
-}
-
-char *
-wimlib_strdup(const char *str)
-{
- size_t size;
- char *p;
-
- size = strlen(str);
- p = MALLOC(size + 1);
- if (p)
- memcpy(p, str, size + 1);
- return p;
-}
-
-#ifdef __WIN32__
-wchar_t *
-wimlib_wcsdup(const wchar_t *str)
+memdup(const void *mem, size_t size)
{
- size_t size;
- wchar_t *p;
-
- size = wcslen(str);
- p = MALLOC((size + 1) * sizeof(wchar_t));
- if (p)
- memcpy(p, str, (size + 1) * sizeof(wchar_t));
- return p;
+ void *ptr = MALLOC(size);
+ if (ptr)
+ ptr = memcpy(ptr, mem, size);
+ return ptr;
}
-#endif
-
-extern void
-xml_set_memory_allocator(void *(*malloc_func)(size_t),
- void (*free_func)(void *),
- void *(*realloc_func)(void *, size_t));
-#endif
+/* API function documented in wimlib.h */
WIMLIBAPI int
wimlib_set_memory_allocator(void *(*malloc_func)(size_t),
void (*free_func)(void *),
void *(*realloc_func)(void *, size_t))
{
-#ifdef ENABLE_CUSTOM_MEMORY_ALLOCATOR
wimlib_malloc_func = malloc_func ? malloc_func : malloc;
wimlib_free_func = free_func ? free_func : free;
wimlib_realloc_func = realloc_func ? realloc_func : realloc;
-
- xml_set_memory_allocator(wimlib_malloc_func, wimlib_free_func,
- wimlib_realloc_func);
return 0;
-#else
- ERROR("Cannot set custom memory allocator functions:");
- ERROR("wimlib was compiled with the --without-custom-memory-allocator "
- "flag");
- return WIMLIB_ERR_UNSUPPORTED;
-#endif
}
-static bool seeded = false;
+/*******************
+ * String utilities
+ *******************/
-static void
-seed_random()
+#ifndef HAVE_MEMPCPY
+void *mempcpy(void *dst, const void *src, size_t n)
{
- srand(time(NULL) * getpid());
- seeded = true;
-}
-
-/* Fills @n characters pointed to by @p with random alphanumeric characters. */
-void
-randomize_char_array_with_alnum(tchar p[], size_t n)
-{
- if (!seeded)
- seed_random();
- while (n--) {
- int r = rand() % 62;
- if (r < 26)
- *p++ = r + 'a';
- else if (r < 52)
- *p++ = r - 26 + 'A';
- else
- *p++ = r - 52 + '0';
- }
-}
-
-/* Fills @n bytes pointer to by @p with random numbers. */
-void
-randomize_byte_array(u8 *p, size_t n)
-{
- if (!seeded)
- seed_random();
- while (n--)
- *p++ = rand();
-}
-
-const tchar *
-path_basename_with_len(const tchar *path, size_t len)
-{
- const tchar *p = &path[len] - 1;
-
- /* Trailing slashes. */
- while (1) {
- if (p == path - 1)
- return T("");
- if (*p != T('/'))
- break;
- p--;
- }
-
- while ((p != path - 1) && *p != T('/'))
- p--;
-
- return p + 1;
+ return memcpy(dst, src, n) + n;
}
+#endif
-/* Like the basename() function, but does not modify @path; it just returns a
- * pointer to it. */
-const tchar *
-path_basename(const tchar *path)
-{
- return path_basename_with_len(path, tstrlen(path));
-}
+/**************************
+ * Random number generation
+ **************************/
+#ifndef _WIN32
/*
- * Returns a pointer to the part of @path following the first colon in the last
- * path component, or NULL if the last path component does not contain a colon.
+ * Generate @n cryptographically secure random bytes (thread-safe)
+ *
+ * This is the UNIX version. It uses the Linux getrandom() system call if
+ * available; otherwise, it falls back to reading from /dev/urandom.
*/
-const tchar *
-path_stream_name(const tchar *path)
-{
- const tchar *base = path_basename(path);
- const tchar *stream_name = tstrchr(base, T(':'));
- if (!stream_name)
- return NULL;
- else
- return stream_name + 1;
-}
-
-u64
-get_wim_timestamp()
-{
- struct timeval tv;
- gettimeofday(&tv, NULL);
- return timeval_to_wim_timestamp(tv);
-}
-
void
-wim_timestamp_to_str(u64 timestamp, tchar *buf, size_t len)
+get_random_bytes(void *p, size_t n)
{
- struct tm tm;
- time_t t = wim_timestamp_to_unix(timestamp);
- gmtime_r(&t, &tm);
- tstrftime(buf, len, T("%a %b %d %H:%M:%S %Y UTC"), &tm);
-}
-
-void
-zap_backslashes(tchar *s)
-{
- if (s) {
- while (*s != T('\0')) {
- if (*s == T('\\'))
- *s = T('/');
- s++;
- }
- }
-}
-
-/* Like read(), but keep trying until everything has been written or we know for
- * sure that there was an error (or end-of-file). */
-size_t
-full_read(int fd, void *buf, size_t count)
-{
- ssize_t bytes_read;
- size_t bytes_remaining;
-
- for (bytes_remaining = count;
- bytes_remaining != 0;
- bytes_remaining -= bytes_read, buf += bytes_read)
- {
- bytes_read = read(fd, buf, bytes_remaining);
- if (bytes_read <= 0) {
- if (bytes_read == 0)
- errno = EIO;
- else if (errno == EINTR)
+ if (n == 0)
+ return;
+#ifdef __NR_getrandom
+ static bool getrandom_unavailable;
+
+ if (getrandom_unavailable)
+ goto try_dev_urandom;
+ do {
+ int res = syscall(__NR_getrandom, p, n, 0);
+ if (unlikely(res < 0)) {
+ if (errno == ENOSYS) {
+ getrandom_unavailable = true;
+ goto try_dev_urandom;
+ }
+ if (errno == EINTR)
continue;
- break;
+ ERROR_WITH_ERRNO("getrandom() failed");
+ wimlib_assert(0);
+ res = 0;
}
+ p += res;
+ n -= res;
+ } while (n != 0);
+ return;
+
+try_dev_urandom:
+ ;
+#endif /* __NR_getrandom */
+ int fd = open("/dev/urandom", O_RDONLY);
+ if (fd < 0) {
+ ERROR_WITH_ERRNO("Unable to open /dev/urandom");
+ wimlib_assert(0);
}
- return count - bytes_remaining;
-}
-
-/* Like write(), but keep trying until everything has been written or we know
- * for sure that there was an error. */
-size_t
-full_write(int fd, const void *buf, size_t count)
-{
- ssize_t bytes_written;
- size_t bytes_remaining;
-
- for (bytes_remaining = count;
- bytes_remaining != 0;
- bytes_remaining -= bytes_written, buf += bytes_written)
- {
- bytes_written = write(fd, buf, bytes_remaining);
- if (bytes_written < 0) {
+ do {
+ int res = read(fd, p, min(n, INT_MAX));
+ if (unlikely(res < 0)) {
if (errno == EINTR)
continue;
- break;
+ ERROR_WITH_ERRNO("Error reading from /dev/urandom");
+ wimlib_assert(0);
+ res = 0;
}
- }
- return count - bytes_remaining;
+ p += res;
+ n -= res;
+ } while (n != 0);
+ close(fd);
}
+#endif /* !_WIN32 */
-/* Like pread(), but keep trying until everything has been read or we know for
- * sure that there was an error (or end-of-file) */
-size_t
-full_pread(int fd, void *buf, size_t count, off_t offset)
+/*
+ * Generate @n cryptographically secure random alphanumeric characters
+ * (thread-safe)
+ *
+ * This is implemented on top of get_random_bytes(). For efficiency the calls
+ * to get_random_bytes() are batched.
+ */
+void
+get_random_alnum_chars(tchar *p, size_t n)
{
- ssize_t bytes_read;
- size_t bytes_remaining;
-
- for (bytes_remaining = count;
- bytes_remaining != 0;
- bytes_remaining -= bytes_read, buf += bytes_read,
- offset += bytes_read)
- {
- bytes_read = pread(fd, buf, bytes_remaining, offset);
- if (bytes_read <= 0) {
- if (bytes_read == 0)
- errno = EIO;
- else if (errno == EINTR)
- continue;
- break;
- }
- }
- return count - bytes_remaining;
-}
+ u32 r[64];
+ int r_idx = 0;
+ int r_end = 0;
-/* Like pwrite(), but keep trying until everything has been written or we know
- * for sure that there was an error. */
-size_t
-full_pwrite(int fd, const void *buf, size_t count, off_t offset)
-{
- ssize_t bytes_written;
- size_t bytes_remaining;
-
- for (bytes_remaining = count;
- bytes_remaining != 0;
- bytes_remaining -= bytes_written, buf += bytes_written,
- offset += bytes_written)
- {
- bytes_written = pwrite(fd, buf, bytes_remaining, offset);
- if (bytes_written < 0) {
- if (errno == EINTR)
- continue;
- break;
+ for (; n != 0; p++, n--) {
+ tchar x;
+
+ if (r_idx >= r_end) {
+ r_idx = 0;
+ r_end = min(n, ARRAY_LEN(r));
+ get_random_bytes(r, r_end * sizeof(r[0]));
}
+
+ STATIC_ASSERT(sizeof(r[0]) == sizeof(u32));
+ while (unlikely(r[r_idx] >= UINT32_MAX - (UINT32_MAX % 62)))
+ get_random_bytes(&r[r_idx], sizeof(r[0]));
+
+ x = r[r_idx++] % 62;
+
+ if (x < 26)
+ *p = 'a' + x;
+ else if (x < 52)
+ *p = 'A' + x - 26;
+ else
+ *p = '0' + x - 52;
}
- return count - bytes_remaining;
}
-/* Like writev(), but keep trying until everything has been written or we know
- * for sure that there was an error. */
-size_t
-full_writev(int fd, struct iovec *iov, int iovcnt)
-{
- size_t total_bytes_written = 0;
- while (iovcnt > 0) {
- ssize_t bytes_written;
+/************************
+ * System information
+ ************************/
- bytes_written = writev(fd, iov, iovcnt);
- if (bytes_written < 0) {
- if (errno == EINTR)
- continue;
- break;
- }
- total_bytes_written += bytes_written;
- while (bytes_written) {
- if (bytes_written >= iov[0].iov_len) {
- bytes_written -= iov[0].iov_len;
- iov++;
- iovcnt--;
- } else {
- iov[0].iov_base += bytes_written;
- iov[0].iov_len -= bytes_written;
- bytes_written = 0;
- }
- }
+#ifndef _WIN32
+unsigned
+get_available_cpus(void)
+{
+ long n = sysconf(_SC_NPROCESSORS_ONLN);
+ if (n < 1 || n >= UINT_MAX) {
+ WARNING("Failed to determine number of processors; assuming 1.");
+ return 1;
}
- return total_bytes_written;
+ return n;
}
+#endif /* !_WIN32 */
-off_t
-filedes_offset(filedes_t fd)
+#ifndef _WIN32
+u64
+get_available_memory(void)
{
- return lseek(fd, 0, SEEK_CUR);
+#if defined(_SC_PAGESIZE) && defined(_SC_PHYS_PAGES)
+ long page_size = sysconf(_SC_PAGESIZE);
+ long num_pages = sysconf(_SC_PHYS_PAGES);
+ if (page_size <= 0 || num_pages <= 0)
+ goto default_size;
+ return ((u64)page_size * (u64)num_pages);
+#else
+ int mib[2] = {CTL_HW, HW_MEMSIZE};
+ u64 memsize;
+ size_t len = sizeof(memsize);
+ if (sysctl(mib, ARRAY_LEN(mib), &memsize, &len, NULL, 0) < 0 || len != 8)
+ goto default_size;
+ return memsize;
+#endif
+
+default_size:
+ WARNING("Failed to determine available memory; assuming 1 GiB");
+ return (u64)1 << 30;
}
+#endif /* !_WIN32 */
git://wimlib.net / wimlib / blobdiff