X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=src%2Ftac.c;h=20a45bfc2273a368ae35f4c1b46a86ca1a3cc62a;hb=77da73c75432f3c5b4beebae7b0797a1e33160bc;hp=be8f3abccbfad7664691d869ba50ea470d6d45f0;hpb=03911ef780eae7d060963bf01ccaf594779b9420;p=platform%2Fupstream%2Fcoreutils.git diff --git a/src/tac.c b/src/tac.c index be8f3ab..20a45bf 100644 --- a/src/tac.c +++ b/src/tac.c @@ -1,5 +1,5 @@ /* tac - concatenate and print files in reverse - Copyright (C) 1988-1991, 1995-2006, 2008 Free Software Foundation, Inc. + Copyright (C) 1988-2013 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 @@ -26,7 +26,7 @@ Options: -b, --before The separator is attached to the beginning - of the record that it precedes in the file. + of the record that it precedes in the file. -r, --regex The separator is a regular expression. -s, --separator=separator Use SEPARATOR as the record separator. @@ -44,13 +44,14 @@ tac -r -s '.\| #include #include "error.h" +#include "filenamecat.h" #include "quote.h" #include "quotearg.h" #include "safe-read.h" #include "stdlib--.h" #include "xfreopen.h" -/* The official name of this program (e.g., no `g' prefix). */ +/* The official name of this program (e.g., no 'g' prefix). */ #define PROGRAM_NAME "tac" #define AUTHORS \ @@ -82,32 +83,32 @@ static char const *separator; /* True if we have ever read standard input. */ static bool have_read_stdin = false; -/* If true, print `separator' along with the record preceding it +/* If true, print 'separator' along with the record preceding it in the file; otherwise with the record following it. */ static bool separator_ends_record; -/* 0 if `separator' is to be matched as a regular expression; - otherwise, the length of `separator', used as a sentinel to +/* 0 if 'separator' is to be matched as a regular expression; + otherwise, the length of 'separator', used as a sentinel to stop the search. */ static size_t sentinel_length; -/* The length of a match with `separator'. If `sentinel_length' is 0, - `match_length' is computed every time a match succeeds; - otherwise, it is simply the length of `separator'. */ +/* The length of a match with 'separator'. If 'sentinel_length' is 0, + 'match_length' is computed every time a match succeeds; + otherwise, it is simply the length of 'separator'. */ static size_t match_length; /* The input buffer. */ static char *G_buffer; -/* The number of bytes to read at once into `buffer'. */ +/* The number of bytes to read at once into 'buffer'. */ static size_t read_size; -/* The size of `buffer'. This is read_size * 2 + sentinel_length + 2. - The extra 2 bytes allow `past_end' to have a value beyond the - end of `G_buffer' and `match_start' to run off the front of `G_buffer'. */ +/* The size of 'buffer'. This is read_size * 2 + sentinel_length + 2. + The extra 2 bytes allow 'past_end' to have a value beyond the + end of 'G_buffer' and 'match_start' to run off the front of 'G_buffer'. */ static size_t G_buffer_size; -/* The compiled regular expression representing `separator'. */ +/* The compiled regular expression representing 'separator'. */ static struct re_pattern_buffer compiled_separator; static char compiled_separator_fastmap[UCHAR_MAX + 1]; static struct re_registers regs; @@ -126,14 +127,13 @@ void usage (int status) { if (status != EXIT_SUCCESS) - fprintf (stderr, _("Try `%s --help' for more information.\n"), - program_name); + emit_try_help (); else { printf (_("\ Usage: %s [OPTION]... [FILE]...\n\ "), - program_name); + program_name); fputs (_("\ Write each FILE to standard output, last line first.\n\ With no FILE, or when FILE is -, read standard input.\n\ @@ -149,7 +149,7 @@ Mandatory arguments to long options are mandatory for short options too.\n\ "), stdout); fputs (HELP_OPTION_DESCRIPTION, stdout); fputs (VERSION_OPTION_DESCRIPTION, stdout); - emit_bug_reporting_address (); + emit_ancillary_info (); } exit (status); } @@ -193,21 +193,21 @@ output (const char *start, const char *past_end) static bool tac_seekable (int input_fd, const char *file) { - /* Pointer to the location in `G_buffer' where the search for + /* Pointer to the location in 'G_buffer' where the search for the next separator will begin. */ char *match_start; - /* Pointer to one past the rightmost character in `G_buffer' that + /* Pointer to one past the rightmost character in 'G_buffer' that has not been printed yet. */ char *past_end; - /* Length of the record growing in `G_buffer'. */ + /* Length of the record growing in 'G_buffer'. */ size_t saved_record_size; /* Offset in the file of the next read. */ off_t file_pos; - /* True if `output' has not been called yet for any file. + /* True if 'output' has not been called yet for any file. Only used when the separator is attached to the preceding record. */ bool first_time = true; char first_char = *separator; /* Speed optimization, non-regexp. */ @@ -215,12 +215,12 @@ tac_seekable (int input_fd, const char *file) size_t match_length1 = match_length - 1; /* Speed optimization, non-regexp. */ /* Find the size of the input file. */ - file_pos = lseek (input_fd, (off_t) 0, SEEK_END); + file_pos = lseek (input_fd, 0, SEEK_END); if (file_pos < 1) return true; /* It's an empty file. */ /* Arrange for the first read to lop off enough to leave the rest of the - file a multiple of `read_size'. Since `read_size' can change, this may + file a multiple of 'read_size'. Since 'read_size' can change, this may not always hold during the program run, but since it usually will, leave it here for i/o efficiency (page/sector boundaries and all that). Note: the efficiency gain has not been verified. */ @@ -228,7 +228,7 @@ tac_seekable (int input_fd, const char *file) if (saved_record_size == 0) saved_record_size = read_size; file_pos -= saved_record_size; - /* `file_pos' now points to the start of the last (probably partial) block + /* 'file_pos' now points to the start of the last (probably partial) block in the input file. */ if (lseek (input_fd, file_pos, SEEK_SET) < 0) @@ -245,136 +245,136 @@ tac_seekable (int input_fd, const char *file) if (sentinel_length) match_start -= match_length1; - for (;;) + while (true) { - /* Search backward from `match_start' - 1 to `G_buffer' for a match - with `separator'; for speed, use strncmp if `separator' contains no - metacharacters. - If the match succeeds, set `match_start' to point to the start of - the match and `match_length' to the length of the match. - Otherwise, make `match_start' < `G_buffer'. */ + /* Search backward from 'match_start' - 1 to 'G_buffer' for a match + with 'separator'; for speed, use strncmp if 'separator' contains no + metacharacters. + If the match succeeds, set 'match_start' to point to the start of + the match and 'match_length' to the length of the match. + Otherwise, make 'match_start' < 'G_buffer'. */ if (sentinel_length == 0) - { - size_t i = match_start - G_buffer; - regoff_t ri = i; - regoff_t range = 1 - ri; - regoff_t ret; - - if (1 < range) - error (EXIT_FAILURE, 0, _("record too large")); - - if (range == 1 - || ((ret = re_search (&compiled_separator, G_buffer, - i, i - 1, range, ®s)) - == -1)) - match_start = G_buffer - 1; - else if (ret == -2) - { - error (EXIT_FAILURE, 0, - _("error in regular expression search")); - } - else - { - match_start = G_buffer + regs.start[0]; - match_length = regs.end[0] - regs.start[0]; - } - } + { + size_t i = match_start - G_buffer; + regoff_t ri = i; + regoff_t range = 1 - ri; + regoff_t ret; + + if (1 < range) + error (EXIT_FAILURE, 0, _("record too large")); + + if (range == 1 + || ((ret = re_search (&compiled_separator, G_buffer, + i, i - 1, range, ®s)) + == -1)) + match_start = G_buffer - 1; + else if (ret == -2) + { + error (EXIT_FAILURE, 0, + _("error in regular expression search")); + } + else + { + match_start = G_buffer + regs.start[0]; + match_length = regs.end[0] - regs.start[0]; + } + } else - { - /* `match_length' is constant for non-regexp boundaries. */ - while (*--match_start != first_char - || (match_length1 && strncmp (match_start + 1, separator1, - match_length1))) - /* Do nothing. */ ; - } - - /* Check whether we backed off the front of `G_buffer' without finding - a match for `separator'. */ + { + /* 'match_length' is constant for non-regexp boundaries. */ + while (*--match_start != first_char + || (match_length1 && strncmp (match_start + 1, separator1, + match_length1))) + /* Do nothing. */ ; + } + + /* Check whether we backed off the front of 'G_buffer' without finding + a match for 'separator'. */ if (match_start < G_buffer) - { - if (file_pos == 0) - { - /* Hit the beginning of the file; print the remaining record. */ - output (G_buffer, past_end); - return true; - } - - saved_record_size = past_end - G_buffer; - if (saved_record_size > read_size) - { - /* `G_buffer_size' is about twice `read_size', so since - we want to read in another `read_size' bytes before - the data already in `G_buffer', we need to increase - `G_buffer_size'. */ - char *newbuffer; - size_t offset = sentinel_length ? sentinel_length : 1; - ptrdiff_t match_start_offset = match_start - G_buffer; - ptrdiff_t past_end_offset = past_end - G_buffer; - size_t old_G_buffer_size = G_buffer_size; - - read_size *= 2; - G_buffer_size = read_size * 2 + sentinel_length + 2; - if (G_buffer_size < old_G_buffer_size) - xalloc_die (); - newbuffer = xrealloc (G_buffer - offset, G_buffer_size); - newbuffer += offset; - /* Adjust the pointers for the new buffer location. */ - match_start = newbuffer + match_start_offset; - past_end = newbuffer + past_end_offset; - G_buffer = newbuffer; - } - - /* Back up to the start of the next bufferfull of the file. */ - if (file_pos >= read_size) - file_pos -= read_size; - else - { - read_size = file_pos; - file_pos = 0; - } - if (lseek (input_fd, file_pos, SEEK_SET) < 0) - error (0, errno, _("%s: seek failed"), quotearg_colon (file)); - - /* Shift the pending record data right to make room for the new. - The source and destination regions probably overlap. */ - memmove (G_buffer + read_size, G_buffer, saved_record_size); - past_end = G_buffer + read_size + saved_record_size; - /* For non-regexp searches, avoid unneccessary scanning. */ - if (sentinel_length) - match_start = G_buffer + read_size; - else - match_start = past_end; - - if (safe_read (input_fd, G_buffer, read_size) != read_size) - { - error (0, errno, _("%s: read error"), quotearg_colon (file)); - return false; - } - } + { + if (file_pos == 0) + { + /* Hit the beginning of the file; print the remaining record. */ + output (G_buffer, past_end); + return true; + } + + saved_record_size = past_end - G_buffer; + if (saved_record_size > read_size) + { + /* 'G_buffer_size' is about twice 'read_size', so since + we want to read in another 'read_size' bytes before + the data already in 'G_buffer', we need to increase + 'G_buffer_size'. */ + char *newbuffer; + size_t offset = sentinel_length ? sentinel_length : 1; + ptrdiff_t match_start_offset = match_start - G_buffer; + ptrdiff_t past_end_offset = past_end - G_buffer; + size_t old_G_buffer_size = G_buffer_size; + + read_size *= 2; + G_buffer_size = read_size * 2 + sentinel_length + 2; + if (G_buffer_size < old_G_buffer_size) + xalloc_die (); + newbuffer = xrealloc (G_buffer - offset, G_buffer_size); + newbuffer += offset; + /* Adjust the pointers for the new buffer location. */ + match_start = newbuffer + match_start_offset; + past_end = newbuffer + past_end_offset; + G_buffer = newbuffer; + } + + /* Back up to the start of the next bufferfull of the file. */ + if (file_pos >= read_size) + file_pos -= read_size; + else + { + read_size = file_pos; + file_pos = 0; + } + if (lseek (input_fd, file_pos, SEEK_SET) < 0) + error (0, errno, _("%s: seek failed"), quotearg_colon (file)); + + /* Shift the pending record data right to make room for the new. + The source and destination regions probably overlap. */ + memmove (G_buffer + read_size, G_buffer, saved_record_size); + past_end = G_buffer + read_size + saved_record_size; + /* For non-regexp searches, avoid unnecessary scanning. */ + if (sentinel_length) + match_start = G_buffer + read_size; + else + match_start = past_end; + + if (safe_read (input_fd, G_buffer, read_size) != read_size) + { + error (0, errno, _("%s: read error"), quotearg_colon (file)); + return false; + } + } else - { - /* Found a match of `separator'. */ - if (separator_ends_record) - { - char *match_end = match_start + match_length; - - /* If this match of `separator' isn't at the end of the - file, print the record. */ - if (!first_time || match_end != past_end) - output (match_end, past_end); - past_end = match_end; - first_time = false; - } - else - { - output (match_start, past_end); - past_end = match_start; - } - - /* For non-regex matching, we can back up. */ - if (sentinel_length > 0) - match_start -= match_length - 1; - } + { + /* Found a match of 'separator'. */ + if (separator_ends_record) + { + char *match_end = match_start + match_length; + + /* If this match of 'separator' isn't at the end of the + file, print the record. */ + if (!first_time || match_end != past_end) + output (match_end, past_end); + past_end = match_end; + first_time = false; + } + else + { + output (match_start, past_end); + past_end = match_start; + } + + /* For non-regex matching, we can back up. */ + if (sentinel_length > 0) + match_start -= match_length - 1; + } } } @@ -417,90 +417,115 @@ record_or_unlink_tempfile (char const *fn, FILE *fp ATTRIBUTE_UNUSED) #endif -/* Copy from file descriptor INPUT_FD (corresponding to the named FILE) to - a temporary file, and set *G_TMP and *G_TEMPFILE to the resulting stream - and file name. Return true if successful. */ - +/* A wrapper around mkstemp that gives us both an open stream pointer, + FP, and the corresponding FILE_NAME. Always return the same FP/name + pair, rewinding/truncating it upon each reuse. */ static bool -copy_to_temp (FILE **g_tmp, char **g_tempfile, int input_fd, char const *file) +temp_stream (FILE **fp, char **file_name) { - static char *template = NULL; - static char const *tempdir; - char *tempfile; - FILE *tmp; - int fd; - - if (template == NULL) + static char *tempfile = NULL; + static FILE *tmp_fp; + if (tempfile == NULL) { - char const * const Template = "%s/tacXXXXXX"; - tempdir = getenv ("TMPDIR"); + char const *t = getenv ("TMPDIR"); + char const *tempdir = t ? t : DEFAULT_TMPDIR; + tempfile = mfile_name_concat (tempdir, "tacXXXXXX", NULL); if (tempdir == NULL) - tempdir = DEFAULT_TMPDIR; - - /* Subtract 2 for `%s' and add 1 for the trailing NUL byte. */ - template = xmalloc (strlen (tempdir) + strlen (Template) - 2 + 1); - sprintf (template, Template, tempdir); + { + error (0, 0, _("memory exhausted")); + return false; + } + + /* FIXME: there's a small window between a successful mkstemp call + and the unlink that's performed by record_or_unlink_tempfile. + If we're interrupted in that interval, this code fails to remove + the temporary file. On systems that define DONT_UNLINK_WHILE_OPEN, + the window is much larger -- it extends to the atexit-called + unlink_tempfile. + FIXME: clean up upon fatal signal. Don't block them, in case + $TMPFILE is a remote file system. */ + + int fd = mkstemp (tempfile); + if (fd < 0) + { + error (0, errno, _("failed to create temporary file in %s"), + quote (tempdir)); + goto Reset; + } + + tmp_fp = fdopen (fd, (O_BINARY ? "w+b" : "w+")); + if (! tmp_fp) + { + error (0, errno, _("failed to open %s for writing"), + quote (tempfile)); + close (fd); + unlink (tempfile); + Reset: + free (tempfile); + tempfile = NULL; + return false; + } + + record_or_unlink_tempfile (tempfile, tmp_fp); } - - /* FIXME: there's a small window between a successful mkstemp call - and the unlink that's performed by record_or_unlink_tempfile. - If we're interrupted in that interval, this code fails to remove - the temporary file. On systems that define DONT_UNLINK_WHILE_OPEN, - the window is much larger -- it extends to the atexit-called - unlink_tempfile. - FIXME: clean up upon fatal signal. Don't block them, in case - $TMPFILE is a remote file system. */ - - tempfile = template; - fd = mkstemp (template); - if (fd < 0) + else { - error (0, errno, _("cannot create temporary file in %s"), - quote (tempdir)); - return false; + if (fseeko (tmp_fp, 0, SEEK_SET) < 0 + || ftruncate (fileno (tmp_fp), 0) < 0) + { + error (0, errno, _("failed to rewind stream for %s"), + quote (tempfile)); + return false; + } } - tmp = fdopen (fd, (O_BINARY ? "w+b" : "w+")); - if (! tmp) - { - error (0, errno, _("cannot open %s for writing"), quote (tempfile)); - close (fd); - unlink (tempfile); - return false; - } + *fp = tmp_fp; + *file_name = tempfile; + return true; +} + +/* Copy from file descriptor INPUT_FD (corresponding to the named FILE) to + a temporary file, and set *G_TMP and *G_TEMPFILE to the resulting stream + and file name. Return true if successful. */ - record_or_unlink_tempfile (tempfile, tmp); +static bool +copy_to_temp (FILE **g_tmp, char **g_tempfile, int input_fd, char const *file) +{ + FILE *fp; + char *file_name; + if (!temp_stream (&fp, &file_name)) + return false; while (1) { size_t bytes_read = safe_read (input_fd, G_buffer, read_size); if (bytes_read == 0) - break; + break; if (bytes_read == SAFE_READ_ERROR) - { - error (0, errno, _("%s: read error"), quotearg_colon (file)); - goto Fail; - } - - if (fwrite (G_buffer, 1, bytes_read, tmp) != bytes_read) - { - error (0, errno, _("%s: write error"), quotearg_colon (tempfile)); - goto Fail; - } + { + error (0, errno, _("%s: read error"), quotearg_colon (file)); + goto Fail; + } + + if (fwrite (G_buffer, 1, bytes_read, fp) != bytes_read) + { + error (0, errno, _("%s: write error"), quotearg_colon (file_name)); + goto Fail; + } } - if (fflush (tmp) != 0) + if (fflush (fp) != 0) { - error (0, errno, _("%s: write error"), quotearg_colon (tempfile)); + error (0, errno, _("%s: write error"), quotearg_colon (file_name)); goto Fail; } - *g_tmp = tmp; - *g_tempfile = tempfile; + *g_tmp = fp; + *g_tempfile = file_name; return true; Fail: - fclose (tmp); + fclose (fp); return false; } @@ -512,8 +537,11 @@ tac_nonseekable (int input_fd, const char *file) { FILE *tmp_stream; char *tmp_file; - return (copy_to_temp (&tmp_stream, &tmp_file, input_fd, file) - && tac_seekable (fileno (tmp_stream), tmp_file)); + if (!copy_to_temp (&tmp_stream, &tmp_file, input_fd, file)) + return false; + + bool ok = tac_seekable (fileno (tmp_stream), tmp_file); + return ok; } /* Print FILE in reverse, copying it to a temporary @@ -534,23 +562,24 @@ tac_file (const char *filename) fd = STDIN_FILENO; filename = _("standard input"); if (O_BINARY && ! isatty (STDIN_FILENO)) - xfreopen (NULL, "rb", stdin); + xfreopen (NULL, "rb", stdin); } else { fd = open (filename, O_RDONLY | O_BINARY); if (fd < 0) - { - error (0, errno, _("cannot open %s for reading"), quote (filename)); - return false; - } + { + error (0, errno, _("failed to open %s for reading"), + quote (filename)); + return false; + } } - file_size = lseek (fd, (off_t) 0, SEEK_END); + file_size = lseek (fd, 0, SEEK_END); ok = (file_size < 0 || isatty (fd) - ? tac_nonseekable (fd, filename) - : tac_seekable (fd, filename)); + ? tac_nonseekable (fd, filename) + : tac_seekable (fd, filename)); if (!is_stdin && close (fd) != 0) { @@ -588,23 +617,23 @@ main (int argc, char **argv) while ((optc = getopt_long (argc, argv, "brs:", longopts, NULL)) != -1) { switch (optc) - { - case 'b': - separator_ends_record = false; - break; - case 'r': - sentinel_length = 0; - break; - case 's': - separator = optarg; - if (*separator == 0) - error (EXIT_FAILURE, 0, _("separator cannot be empty")); - break; - case_GETOPT_HELP_CHAR; - case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS); - default: - usage (EXIT_FAILURE); - } + { + case 'b': + separator_ends_record = false; + break; + case 'r': + sentinel_length = 0; + break; + case 's': + separator = optarg; + if (*separator == 0) + error (EXIT_FAILURE, 0, _("separator cannot be empty")); + break; + case_GETOPT_HELP_CHAR; + case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS); + default: + usage (EXIT_FAILURE); + } } if (sentinel_length == 0) @@ -614,9 +643,9 @@ main (int argc, char **argv) compiled_separator.fastmap = compiled_separator_fastmap; compiled_separator.translate = NULL; error_message = re_compile_pattern (separator, strlen (separator), - &compiled_separator); + &compiled_separator); if (error_message) - error (EXIT_FAILURE, 0, "%s", error_message); + error (EXIT_FAILURE, 0, "%s", error_message); } else match_length = sentinel_length = strlen (separator); @@ -625,7 +654,7 @@ main (int argc, char **argv) while (sentinel_length >= read_size / 2) { if (SIZE_MAX / 2 < read_size) - xalloc_die (); + xalloc_die (); read_size *= 2; } half_buffer_size = read_size + sentinel_length + 1; @@ -635,7 +664,7 @@ main (int argc, char **argv) G_buffer = xmalloc (G_buffer_size); if (sentinel_length) { - strcpy (G_buffer, separator); + memcpy (G_buffer, separator, sentinel_length + 1); G_buffer += sentinel_length; } else @@ -644,8 +673,8 @@ main (int argc, char **argv) } file = (optind < argc - ? (char const *const *) &argv[optind] - : default_file_list); + ? (char const *const *) &argv[optind] + : default_file_list); if (O_BINARY && ! isatty (STDOUT_FILENO)) xfreopen (NULL, "wb", stdout); @@ -661,6 +690,15 @@ main (int argc, char **argv) output ((char *) NULL, (char *) NULL); if (have_read_stdin && close (STDIN_FILENO) < 0) - error (EXIT_FAILURE, errno, "-"); + { + error (0, errno, "-"); + ok = false; + } + +#ifdef lint + size_t offset = sentinel_length ? sentinel_length : 1; + free (G_buffer - offset); +#endif + exit (ok ? EXIT_SUCCESS : EXIT_FAILURE); }