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-rw-r--r--lib/randread.c297
1 files changed, 0 insertions, 297 deletions
diff --git a/lib/randread.c b/lib/randread.c
deleted file mode 100644
index 9f65db676..000000000
--- a/lib/randread.c
+++ /dev/null
@@ -1,297 +0,0 @@
-/* Generate buffers of random data.
-
- Copyright (C) 2006 Free Software Foundation, Inc.
-
- This program 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.
-
- This program 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 details.
-
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>. */
-
-/* Written by Paul Eggert. */
-
-#include <config.h>
-
-#include "randread.h"
-
-#include <errno.h>
-#include <error.h>
-#include <exitfail.h>
-#include <quotearg.h>
-#include <stdbool.h>
-#include <stdint.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include "gettext.h"
-#define _(msgid) gettext (msgid)
-
-#include "rand-isaac.h"
-#include "stdio-safer.h"
-#include "unlocked-io.h"
-#include "xalloc.h"
-
-#ifndef MIN
-# define MIN(a, b) ((a) < (b) ? (a) : (b))
-#endif
-
-#ifndef __attribute__
-# if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8) || __STRICT_ANSI__
-# define __attribute__(x)
-# endif
-#endif
-
-#ifndef ATTRIBUTE_UNUSED
-# define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
-#endif
-
-#if _STRING_ARCH_unaligned
-# define ALIGNED_POINTER(ptr, type) true
-#else
-# define alignof(type) offsetof (struct { char c; type x; }, x)
-# define ALIGNED_POINTER(ptr, type) ((size_t) (ptr) % alignof (type) == 0)
-#endif
-
-#ifndef DEFAULT_RANDOM_FILE
-# define DEFAULT_RANDOM_FILE "/dev/urandom"
-#endif
-
-/* The maximum buffer size used for reads of random data. Using the
- value 2 * ISAAC_BYTES makes this the largest power of two that
- would not otherwise cause struct randread_source to grow. */
-#define RANDREAD_BUFFER_SIZE (2 * ISAAC_BYTES)
-
-/* A source of random data for generating random buffers. */
-struct randread_source
-{
- /* Stream to read random bytes from. If null, the behavior is
- undefined; the current implementation uses ISAAC in this case,
- but this is for old-fashioned implementations that lack
- /dev/urandom and callers should not rely on this. */
- FILE *source;
-
- /* Function to call, and its argument, if there is an input error or
- end of file when reading from the stream; errno is nonzero if
- there was an error. If this function returns, it should fix the
- problem before returning. The default handler assumes that
- handler_arg is the file name of the source. */
- void (*handler) (void const *);
- void const *handler_arg;
-
- /* The buffer for SOURCE. It's kept here to simplify storage
- allocation and to make it easier to clear out buffered random
- data. */
- union
- {
- /* The stream buffer, if SOURCE is not null. */
- char c[RANDREAD_BUFFER_SIZE];
-
- /* The buffered ISAAC pseudorandom buffer, if SOURCE is null. */
- struct isaac
- {
- /* The number of bytes that are buffered at the end of data.b. */
- size_t buffered;
-
- /* State of the ISAAC generator. */
- struct isaac_state state;
-
- /* Up to a buffer's worth of pseudorandom data. */
- union
- {
- uint32_t w[ISAAC_WORDS];
- unsigned char b[ISAAC_BYTES];
- } data;
- } isaac;
- } buf;
-};
-
-
-/* The default error handler. */
-
-static void
-randread_error (void const *file_name)
-{
- if (file_name)
- error (exit_failure, errno,
- _(errno == 0 ? "%s: end of file" : "%s: read error"),
- quotearg_colon (file_name));
- abort ();
-}
-
-/* Simply return a new randread_source object with the default error
- handler. */
-
-static struct randread_source *
-simple_new (FILE *source, void const *handler_arg)
-{
- struct randread_source *s = xmalloc (sizeof *s);
- s->source = source;
- s->handler = randread_error;
- s->handler_arg = handler_arg;
- return s;
-}
-
-/* Create and initialize a random data source from NAME, or use a
- reasonable default source if NAME is null. BYTES_BOUND is an upper
- bound on the number of bytes that will be needed. If zero, it is a
- hard bound; otherwise it is just an estimate.
-
- If NAME is not null, NAME is saved for use as the argument of the
- default handler. Unless a non-default handler is used, NAME's
- lifetime should be at least that of the returned value.
-
- Return NULL (setting errno) on failure. */
-
-struct randread_source *
-randread_new (char const *name, size_t bytes_bound)
-{
- if (bytes_bound == 0)
- return simple_new (NULL, NULL);
- else
- {
- char const *file_name = (name ? name : DEFAULT_RANDOM_FILE);
- FILE *source = fopen_safer (file_name, "rb");
- struct randread_source *s;
-
- if (! source)
- {
- if (name)
- return NULL;
- file_name = NULL;
- }
-
- s = simple_new (source, file_name);
-
- if (source)
- setvbuf (source, s->buf.c, _IOFBF, MIN (sizeof s->buf.c, bytes_bound));
- else
- {
- s->buf.isaac.buffered = 0;
- isaac_seed (&s->buf.isaac.state);
- }
-
- return s;
- }
-}
-
-
-/* Set S's handler and its argument. HANDLER (HANDLER_ARG) is called
- when there is a read error or end of file from the random data
- source; errno is nonzero if there was an error. If HANDLER
- returns, it should fix the problem before returning. The default
- handler assumes that handler_arg is the file name of the source; it
- does not return. */
-
-void
-randread_set_handler (struct randread_source *s, void (*handler) (void const *))
-{
- s->handler = handler;
-}
-
-void
-randread_set_handler_arg (struct randread_source *s, void const *handler_arg)
-{
- s->handler_arg = handler_arg;
-}
-
-
-/* Place SIZE random bytes into the buffer beginning at P, using
- the stream in S. */
-
-static void
-readsource (struct randread_source *s, unsigned char *p, size_t size)
-{
- for (;;)
- {
- size_t inbytes = fread (p, sizeof *p, size, s->source);
- int fread_errno = errno;
- p += inbytes;
- size -= inbytes;
- if (size == 0)
- break;
- errno = (ferror (s->source) ? fread_errno : 0);
- s->handler (s->handler_arg);
- }
-}
-
-
-/* Place SIZE pseudorandom bytes into the buffer beginning at P, using
- the buffered ISAAC generator in ISAAC. */
-
-static void
-readisaac (struct isaac *isaac, unsigned char *p, size_t size)
-{
- size_t inbytes = isaac->buffered;
-
- for (;;)
- {
- if (size <= inbytes)
- {
- memcpy (p, isaac->data.b + ISAAC_BYTES - inbytes, size);
- isaac->buffered = inbytes - size;
- return;
- }
-
- memcpy (p, isaac->data.b + ISAAC_BYTES - inbytes, inbytes);
- p += inbytes;
- size -= inbytes;
-
- /* If P is aligned, write to *P directly to avoid the overhead
- of copying from the buffer. */
- if (ALIGNED_POINTER (p, uint32_t))
- {
- uint32_t *wp = (uint32_t *) p;
- while (ISAAC_BYTES <= size)
- {
- isaac_refill (&isaac->state, wp);
- wp += ISAAC_WORDS;
- size -= ISAAC_BYTES;
- if (size == 0)
- {
- isaac->buffered = 0;
- return;
- }
- }
- p = (unsigned char *) wp;
- }
-
- isaac_refill (&isaac->state, isaac->data.w);
- inbytes = ISAAC_BYTES;
- }
-}
-
-
-/* Consume random data from *S to generate a random buffer BUF of size
- SIZE. */
-
-void
-randread (struct randread_source *s, void *buf, size_t size)
-{
- if (s->source)
- readsource (s, buf, size);
- else
- readisaac (&s->buf.isaac, buf, size);
-}
-
-
-/* Clear *S so that it no longer contains undelivered random data, and
- deallocate any system resources associated with *S. Return 0 if
- successful, a negative number (setting errno) if not (this is rare,
- but can occur in theory if there is an input error). */
-
-int
-randread_free (struct randread_source *s)
-{
- FILE *source = s->source;
- memset (s, 0, sizeof *s);
- free (s);
- return (source ? fclose (source) : 0);
-}
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