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+/* Shuffle lines of text.
+
+ Copyright (C) 2006, 2007 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 2, 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, write to the Free Software
+ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+ Written by Paul Eggert. */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <sys/types.h>
+#include "system.h"
+
+#include "error.h"
+#include "getopt.h"
+#include "quote.h"
+#include "quotearg.h"
+#include "randint.h"
+#include "randperm.h"
+#include "xstrtol.h"
+
+/* The official name of this program (e.g., no `g' prefix). */
+#define PROGRAM_NAME "shuf"
+
+#define AUTHORS "Paul Eggert"
+
+/* The name this program was run with. */
+char *program_name;
+
+void
+usage (int status)
+{
+ if (status != EXIT_SUCCESS)
+ fprintf (stderr, _("Try `%s --help' for more information.\n"),
+ program_name);
+ else
+ {
+ printf (_("\
+Usage: %s [OPTION]... [FILE]\n\
+ or: %s -e [OPTION]... [ARG]...\n\
+ or: %s -i LO-HI [OPTION]...\n\
+"),
+ program_name, program_name, program_name);
+ fputs (_("\
+Write a random permutation of the input lines to standard output.\n\
+\n\
+"), stdout);
+ fputs (_("\
+Mandatory arguments to long options are mandatory for short options too.\n\
+"), stdout);
+ fputs (_("\
+ -e, --echo treat each ARG as an input line\n\
+ -i, --input-range=LO-HI treat each number LO through HI as an input line\n\
+ -n, --head-lines=LINES output at most LINES lines\n\
+ -o, --output=FILE write result to FILE instead of standard output\n\
+ --random-source=FILE get random bytes from FILE (default /dev/urandom)\n\
+ -z, --zero-terminated end lines with 0 byte, not newline\n\
+"), stdout);
+ fputs (HELP_OPTION_DESCRIPTION, stdout);
+ fputs (VERSION_OPTION_DESCRIPTION, stdout);
+ fputs (_("\
+\n\
+With no FILE, or when FILE is -, read standard input.\n\
+"), stdout);
+ printf (_("\nReport bugs to <%s>.\n"), PACKAGE_BUGREPORT);
+ }
+
+ exit (status);
+}
+
+/* For long options that have no equivalent short option, use a
+ non-character as a pseudo short option, starting with CHAR_MAX + 1. */
+enum
+{
+ RANDOM_SOURCE_OPTION = CHAR_MAX + 1
+};
+
+static struct option const long_opts[] =
+{
+ {"echo", no_argument, NULL, 'e'},
+ {"input-range", required_argument, NULL, 'i'},
+ {"head-count", required_argument, NULL, 'n'},
+ {"output", required_argument, NULL, 'o'},
+ {"random-source", required_argument, NULL, RANDOM_SOURCE_OPTION},
+ {"zero-terminated", no_argument, NULL, 'z'},
+ {GETOPT_HELP_OPTION_DECL},
+ {GETOPT_VERSION_OPTION_DECL},
+ {0, 0, 0, 0},
+};
+
+static bool
+input_numbers_option_used (size_t lo_input, size_t hi_input)
+{
+ return ! (lo_input == SIZE_MAX && hi_input == 0);
+}
+
+static void
+input_from_argv (char **operand, int n_operands, char eolbyte)
+{
+ char *p;
+ size_t size = n_operands;
+ int i;
+
+ for (i = 0; i < n_operands; i++)
+ size += strlen (operand[i]);
+ p = xmalloc (size);
+
+ for (i = 0; i < n_operands; i++)
+ {
+ char *p1 = stpcpy (p, operand[i]);
+ operand[i] = p;
+ p = p1;
+ *p++ = eolbyte;
+ }
+
+ operand[n_operands] = p;
+}
+
+/* Return the start of the next line after LINE. The current line
+ ends in EOLBYTE, and is guaranteed to end before LINE + N. */
+
+static char *
+next_line (char *line, char eolbyte, size_t n)
+{
+ char *p = memchr (line, eolbyte, n);
+ return p + 1;
+}
+
+/* Read data from file IN. Input lines are delimited by EOLBYTE;
+ silently append a trailing EOLBYTE if the file ends in some other
+ byte. Store a pointer to the resulting array of lines into *PLINE.
+ Return the number of lines read. Report an error and exit on
+ failure. */
+
+static size_t
+read_input (FILE *in, char eolbyte, char ***pline)
+{
+ char *p;
+ char *buf = NULL;
+ char *lim;
+ size_t alloc = 0;
+ size_t used = 0;
+ size_t next_alloc = (1 << 13) + 1;
+ size_t bytes_to_read;
+ size_t nread;
+ char **line;
+ size_t i;
+ size_t n_lines;
+ int fread_errno;
+ struct stat instat;
+
+ if (fstat (fileno (in), &instat) == 0 && S_ISREG (instat.st_mode))
+ {
+ off_t file_size = instat.st_size;
+ off_t current_offset = ftello (in);
+ if (0 <= current_offset)
+ {
+ off_t remaining_size =
+ (current_offset < file_size ? file_size - current_offset : 0);
+ if (SIZE_MAX - 2 < remaining_size)
+ xalloc_die ();
+ next_alloc = remaining_size + 2;
+ }
+ }
+
+ do
+ {
+ if (alloc <= used + 1)
+ {
+ if (alloc == SIZE_MAX)
+ xalloc_die ();
+ alloc = next_alloc;
+ next_alloc = alloc * 2;
+ if (next_alloc < alloc)
+ next_alloc = SIZE_MAX;
+ buf = xrealloc (buf, alloc);
+ }
+
+ bytes_to_read = alloc - used - 1;
+ nread = fread (buf + used, sizeof (char), bytes_to_read, in);
+ used += nread;
+ }
+ while (nread == bytes_to_read);
+
+ fread_errno = errno;
+
+ if (used && buf[used - 1] != eolbyte)
+ buf[used++] = eolbyte;
+
+ lim = buf + used;
+
+ n_lines = 0;
+ for (p = buf; p < lim; p = next_line (p, eolbyte, lim - p))
+ n_lines++;
+
+ *pline = line = xnmalloc (n_lines + 1, sizeof *line);
+
+ line[0] = p = buf;
+ for (i = 1; i <= n_lines; i++)
+ line[i] = p = next_line (p, eolbyte, lim - p);
+
+ errno = fread_errno;
+ return n_lines;
+}
+
+static int
+write_permuted_output (size_t n_lines, char * const *line, size_t lo_input,
+ size_t const *permutation)
+{
+ size_t i;
+
+ if (line)
+ for (i = 0; i < n_lines; i++)
+ {
+ char * const *p = line + permutation[i];
+ size_t len = p[1] - p[0];
+ if (fwrite (p[0], sizeof *p[0], len, stdout) != len)
+ return -1;
+ }
+ else
+ for (i = 0; i < n_lines; i++)
+ {
+ unsigned long int n = lo_input + permutation[i];
+ if (printf ("%lu\n", n) < 0)
+ return -1;
+ }
+
+ return 0;
+}
+
+int
+main (int argc, char **argv)
+{
+ bool echo = false;
+ size_t lo_input = SIZE_MAX;
+ size_t hi_input = 0;
+ size_t head_lines = SIZE_MAX;
+ char const *outfile = NULL;
+ char *random_source = NULL;
+ char eolbyte = '\n';
+ char **input_lines = NULL;
+
+ int optc;
+ int n_operands;
+ char **operand;
+ size_t n_lines;
+ char **line;
+ struct randint_source *randint_source;
+ size_t *permutation;
+
+ initialize_main (&argc, &argv);
+ program_name = argv[0];
+ setlocale (LC_ALL, "");
+ bindtextdomain (PACKAGE, LOCALEDIR);
+ textdomain (PACKAGE);
+
+ atexit (close_stdout);
+
+ while ((optc = getopt_long (argc, argv, "ei:n:o:z", long_opts, NULL)) != -1)
+ switch (optc)
+ {
+ case 'e':
+ echo = true;
+ break;
+
+ case 'i':
+ {
+ unsigned long int argval = 0;
+ char *p = strchr (optarg, '-');
+ char const *hi_optarg = optarg;
+ bool invalid = !p;
+
+ if (input_numbers_option_used (lo_input, hi_input))
+ error (EXIT_FAILURE, 0, _("multiple -i options specified"));
+
+ if (p)
+ {
+ *p = '\0';
+ invalid = ((xstrtoul (optarg, NULL, 10, &argval, NULL)
+ != LONGINT_OK)
+ || SIZE_MAX < argval);
+ *p = '-';
+ lo_input = argval;
+ hi_optarg = p + 1;
+ }
+
+ invalid |= ((xstrtoul (hi_optarg, NULL, 10, &argval, NULL)
+ != LONGINT_OK)
+ || SIZE_MAX < argval);
+ hi_input = argval;
+ n_lines = hi_input - lo_input + 1;
+ invalid |= ((lo_input <= hi_input) == (n_lines == 0));
+ if (invalid)
+ error (EXIT_FAILURE, 0, _("invalid input range %s"),
+ quote (optarg));
+ }
+ break;
+
+ case 'n':
+ {
+ unsigned long int argval;
+ strtol_error e = xstrtoul (optarg, NULL, 10, &argval, NULL);
+
+ if (e == LONGINT_OK)
+ head_lines = MIN (head_lines, argval);
+ else if (e != LONGINT_OVERFLOW)
+ error (EXIT_FAILURE, 0, _("invalid line count %s"),
+ quote (optarg));
+ }
+ break;
+
+ case 'o':
+ if (outfile && !STREQ (outfile, optarg))
+ error (EXIT_FAILURE, 0, _("multiple output files specified"));
+ outfile = optarg;
+ break;
+
+ case RANDOM_SOURCE_OPTION:
+ if (random_source && !STREQ (random_source, optarg))
+ error (EXIT_FAILURE, 0, _("multiple random sources specified"));
+ random_source = optarg;
+ break;
+
+ case 'z':
+ eolbyte = '\0';
+ break;
+
+ case_GETOPT_HELP_CHAR;
+ case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS);
+ default:
+ usage (EXIT_FAILURE);
+ }
+
+ n_operands = argc - optind;
+ operand = argv + optind;
+
+ if (echo)
+ {
+ if (input_numbers_option_used (lo_input, hi_input))
+ error (EXIT_FAILURE, 0, _("cannot combine -e and -i options"));
+ input_from_argv (operand, n_operands, eolbyte);
+ n_lines = n_operands;
+ line = operand;
+ }
+ else if (input_numbers_option_used (lo_input, hi_input))
+ {
+ if (n_operands)
+ {
+ error (0, 0, _("extra operand %s\n"), quote (operand[0]));
+ usage (EXIT_FAILURE);
+ }
+ n_lines = hi_input - lo_input + 1;
+ line = NULL;
+ }
+ else
+ {
+ switch (n_operands)
+ {
+ case 0:
+ break;
+
+ case 1:
+ if (! (STREQ (operand[0], "-") || freopen (operand[0], "r", stdin)))
+ error (EXIT_FAILURE, errno, "%s", operand[0]);
+ break;
+
+ default:
+ error (0, 0, _("extra operand %s"), quote (operand[1]));
+ usage (EXIT_FAILURE);
+ }
+
+ n_lines = read_input (stdin, eolbyte, &input_lines);
+ line = input_lines;
+ }
+
+ head_lines = MIN (head_lines, n_lines);
+
+ randint_source = randint_all_new (random_source,
+ randperm_bound (head_lines, n_lines));
+ if (! randint_source)
+ error (EXIT_FAILURE, errno, "%s", quotearg_colon (random_source));
+
+ /* Close stdin now, rather than earlier, so that randint_all_new
+ doesn't have to worry about opening something other than
+ stdin. */
+ if (! (echo || input_numbers_option_used (lo_input, hi_input))
+ && (ferror (stdin) || fclose (stdin) != 0))
+ error (EXIT_FAILURE, errno, _("read error"));
+
+ permutation = randperm_new (randint_source, head_lines, n_lines);
+
+ if (outfile && ! freopen (outfile, "w", stdout))
+ error (EXIT_FAILURE, errno, "%s", quotearg_colon (outfile));
+ if (write_permuted_output (head_lines, line, lo_input, permutation) != 0)
+ error (EXIT_FAILURE, errno, _("write error"));
+
+#ifdef lint
+ free (permutation);
+ randint_all_free (randint_source);
+ if (input_lines)
+ {
+ free (input_lines[0]);
+ free (input_lines);
+ }
+#endif
+
+ return EXIT_SUCCESS;
+}
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