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Diffstat (limited to 'src/comm.c')
| -rw-r--r-- | src/comm.c | 499 |
1 files changed, 499 insertions, 0 deletions
diff --git a/src/comm.c b/src/comm.c new file mode 100644 index 0000000..2bf8094 --- /dev/null +++ b/src/comm.c @@ -0,0 +1,499 @@ +/* comm -- compare two sorted files line by line. + Copyright (C) 1986-2020 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 <https://www.gnu.org/licenses/>. */ + +/* Written by Richard Stallman and David MacKenzie. */ + +#include <config.h> + +#include <getopt.h> +#include <sys/types.h> +#include "system.h" +#include "linebuffer.h" +#include "die.h" +#include "error.h" +#include "fadvise.h" +#include "hard-locale.h" +#include "quote.h" +#include "stdio--.h" +#include "memcmp2.h" +#include "xmemcoll.h" + +/* The official name of this program (e.g., no 'g' prefix). */ +#define PROGRAM_NAME "comm" + +#define AUTHORS \ + proper_name ("Richard M. Stallman"), \ + proper_name ("David MacKenzie") + +/* Undefine, to avoid warning about redefinition on some systems. */ +#undef min +#define min(x, y) ((x) < (y) ? (x) : (y)) + +/* True if the LC_COLLATE locale is hard. */ +static bool hard_LC_COLLATE; + +/* If true, print lines that are found only in file 1. */ +static bool only_file_1; + +/* If true, print lines that are found only in file 2. */ +static bool only_file_2; + +/* If true, print lines that are found in both files. */ +static bool both; + +/* If nonzero, we have seen at least one unpairable line. */ +static bool seen_unpairable; + +/* If nonzero, we have warned about disorder in that file. */ +static bool issued_disorder_warning[2]; + +/* line delimiter. */ +static unsigned char delim = '\n'; + +/* If true, print a summary. */ +static bool total_option; + +/* If nonzero, check that the input is correctly ordered. */ +static enum + { + CHECK_ORDER_DEFAULT, + CHECK_ORDER_ENABLED, + CHECK_ORDER_DISABLED + } check_input_order; + +/* Output columns will be delimited with this string, which may be set + on the command-line with --output-delimiter=STR. */ +static char const *col_sep = "\t"; +static size_t col_sep_len = 0; + +/* For long options that have no equivalent short option, use a + non-character as a pseudo short option, starting with CHAR_MAX + 1. */ +enum +{ + CHECK_ORDER_OPTION = CHAR_MAX + 1, + NOCHECK_ORDER_OPTION, + OUTPUT_DELIMITER_OPTION, + TOTAL_OPTION +}; + +static struct option const long_options[] = +{ + {"check-order", no_argument, NULL, CHECK_ORDER_OPTION}, + {"nocheck-order", no_argument, NULL, NOCHECK_ORDER_OPTION}, + {"output-delimiter", required_argument, NULL, OUTPUT_DELIMITER_OPTION}, + {"total", no_argument, NULL, TOTAL_OPTION}, + {"zero-terminated", no_argument, NULL, 'z'}, + {GETOPT_HELP_OPTION_DECL}, + {GETOPT_VERSION_OPTION_DECL}, + {NULL, 0, NULL, 0} +}; + + +void +usage (int status) +{ + if (status != EXIT_SUCCESS) + emit_try_help (); + else + { + printf (_("\ +Usage: %s [OPTION]... FILE1 FILE2\n\ +"), + program_name); + fputs (_("\ +Compare sorted files FILE1 and FILE2 line by line.\n\ +"), stdout); + fputs (_("\ +\n\ +When FILE1 or FILE2 (not both) is -, read standard input.\n\ +"), stdout); + fputs (_("\ +\n\ +With no options, produce three-column output. Column one contains\n\ +lines unique to FILE1, column two contains lines unique to FILE2,\n\ +and column three contains lines common to both files.\n\ +"), stdout); + fputs (_("\ +\n\ + -1 suppress column 1 (lines unique to FILE1)\n\ + -2 suppress column 2 (lines unique to FILE2)\n\ + -3 suppress column 3 (lines that appear in both files)\n\ +"), stdout); + fputs (_("\ +\n\ + --check-order check that the input is correctly sorted, even\n\ + if all input lines are pairable\n\ + --nocheck-order do not check that the input is correctly sorted\n\ +"), stdout); + fputs (_("\ + --output-delimiter=STR separate columns with STR\n\ +"), stdout); + fputs (_("\ + --total output a summary\n\ +"), stdout); + fputs (_("\ + -z, --zero-terminated line delimiter is NUL, not newline\n\ +"), stdout); + fputs (HELP_OPTION_DESCRIPTION, stdout); + fputs (VERSION_OPTION_DESCRIPTION, stdout); + fputs (_("\ +\n\ +Note, comparisons honor the rules specified by 'LC_COLLATE'.\n\ +"), stdout); + printf (_("\ +\n\ +Examples:\n\ + %s -12 file1 file2 Print only lines present in both file1 and file2.\n\ + %s -3 file1 file2 Print lines in file1 not in file2, and vice versa.\n\ +"), + program_name, program_name); + emit_ancillary_info (PROGRAM_NAME); + } + exit (status); +} + +/* Output the line in linebuffer LINE to stream STREAM + provided the switches say it should be output. + CLASS is 1 for a line found only in file 1, + 2 for a line only in file 2, 3 for a line in both. */ + +static void +writeline (struct linebuffer const *line, FILE *stream, int class) +{ + switch (class) + { + case 1: + if (!only_file_1) + return; + break; + + case 2: + if (!only_file_2) + return; + if (only_file_1) + fwrite (col_sep, 1, col_sep_len, stream); + break; + + case 3: + if (!both) + return; + if (only_file_1) + fwrite (col_sep, 1, col_sep_len, stream); + if (only_file_2) + fwrite (col_sep, 1, col_sep_len, stream); + break; + } + + fwrite (line->buffer, sizeof (char), line->length, stream); +} + +/* Check that successive input lines PREV and CURRENT from input file + WHATFILE are presented in order. + + If the user specified --nocheck-order, the check is not made. + If the user specified --check-order, the problem is fatal. + Otherwise (the default), the message is simply a warning. + + A message is printed at most once per input file. + + This function was copied (nearly) verbatim from 'src/join.c'. */ + +static void +check_order (struct linebuffer const *prev, + struct linebuffer const *current, + int whatfile) +{ + + if (check_input_order != CHECK_ORDER_DISABLED + && ((check_input_order == CHECK_ORDER_ENABLED) || seen_unpairable)) + { + if (!issued_disorder_warning[whatfile - 1]) + { + int order; + + if (hard_LC_COLLATE) + order = xmemcoll (prev->buffer, prev->length - 1, + current->buffer, current->length - 1); + else + order = memcmp2 (prev->buffer, prev->length - 1, + current->buffer, current->length - 1); + + if (0 < order) + { + error ((check_input_order == CHECK_ORDER_ENABLED + ? EXIT_FAILURE : 0), + 0, _("file %d is not in sorted order"), whatfile); + + /* If we get to here, the message was just a warning, but we + want only to issue it once. */ + issued_disorder_warning[whatfile - 1] = true; + } + } + } +} + +/* Compare INFILES[0] and INFILES[1]. + If either is "-", use the standard input for that file. + Assume that each input file is sorted; + merge them and output the result. */ + +static void +compare_files (char **infiles) +{ + /* For each file, we have four linebuffers in lba. */ + struct linebuffer lba[2][4]; + + /* thisline[i] points to the linebuffer holding the next available line + in file i, or is NULL if there are no lines left in that file. */ + struct linebuffer *thisline[2]; + + /* all_line[i][alt[i][0]] also points to the linebuffer holding the + current line in file i. We keep two buffers of history around so we + can look two lines back when we get to the end of a file. */ + struct linebuffer *all_line[2][4]; + + /* This is used to rotate through the buffers for each input file. */ + int alt[2][3]; + + /* streams[i] holds the input stream for file i. */ + FILE *streams[2]; + + /* Counters for the summary. */ + uintmax_t total[] = {0, 0, 0}; + + int i, j; + + /* Initialize the storage. */ + for (i = 0; i < 2; i++) + { + for (j = 0; j < 4; j++) + { + initbuffer (&lba[i][j]); + all_line[i][j] = &lba[i][j]; + } + alt[i][0] = 0; + alt[i][1] = 0; + alt[i][2] = 0; + streams[i] = (STREQ (infiles[i], "-") ? stdin : fopen (infiles[i], "r")); + if (!streams[i]) + die (EXIT_FAILURE, errno, "%s", quotef (infiles[i])); + + fadvise (streams[i], FADVISE_SEQUENTIAL); + + thisline[i] = readlinebuffer_delim (all_line[i][alt[i][0]], streams[i], + delim); + if (ferror (streams[i])) + die (EXIT_FAILURE, errno, "%s", quotef (infiles[i])); + } + + while (thisline[0] || thisline[1]) + { + int order; + bool fill_up[2] = { false, false }; + + /* Compare the next available lines of the two files. */ + + if (!thisline[0]) + order = 1; + else if (!thisline[1]) + order = -1; + else + { + if (hard_LC_COLLATE) + order = xmemcoll (thisline[0]->buffer, thisline[0]->length - 1, + thisline[1]->buffer, thisline[1]->length - 1); + else + { + size_t len = min (thisline[0]->length, thisline[1]->length) - 1; + order = memcmp (thisline[0]->buffer, thisline[1]->buffer, len); + if (order == 0) + order = (thisline[0]->length < thisline[1]->length + ? -1 + : thisline[0]->length != thisline[1]->length); + } + } + + /* Output the line that is lesser. */ + if (order == 0) + { + /* Line is seen in both files. */ + total[2]++; + writeline (thisline[1], stdout, 3); + } + else + { + seen_unpairable = true; + if (order <= 0) + { + /* Line is seen in file 1 only. */ + total[0]++; + writeline (thisline[0], stdout, 1); + } + else + { + /* Line is seen in file 2 only. */ + total[1]++; + writeline (thisline[1], stdout, 2); + } + } + + /* Step the file the line came from. + If the files match, step both files. */ + if (0 <= order) + fill_up[1] = true; + if (order <= 0) + fill_up[0] = true; + + for (i = 0; i < 2; i++) + if (fill_up[i]) + { + /* Rotate the buffers for this file. */ + alt[i][2] = alt[i][1]; + alt[i][1] = alt[i][0]; + alt[i][0] = (alt[i][0] + 1) & 0x03; + + thisline[i] = readlinebuffer_delim (all_line[i][alt[i][0]], + streams[i], delim); + + if (thisline[i]) + check_order (all_line[i][alt[i][1]], thisline[i], i + 1); + + /* If this is the end of the file we may need to re-check + the order of the previous two lines, since we might have + discovered an unpairable match since we checked before. */ + else if (all_line[i][alt[i][2]]->buffer) + check_order (all_line[i][alt[i][2]], + all_line[i][alt[i][1]], i + 1); + + if (ferror (streams[i])) + die (EXIT_FAILURE, errno, "%s", quotef (infiles[i])); + + fill_up[i] = false; + } + } + + for (i = 0; i < 2; i++) + if (fclose (streams[i]) != 0) + die (EXIT_FAILURE, errno, "%s", quotef (infiles[i])); + + if (total_option) + { + /* Print the summary, minding the column and line delimiters. */ + char buf1[INT_BUFSIZE_BOUND (uintmax_t)]; + char buf2[INT_BUFSIZE_BOUND (uintmax_t)]; + char buf3[INT_BUFSIZE_BOUND (uintmax_t)]; + printf ("%s%s%s%s%s%s%s%c", + umaxtostr (total[0], buf1), col_sep, + umaxtostr (total[1], buf2), col_sep, + umaxtostr (total[2], buf3), col_sep, + _("total"), delim); + } +} + +int +main (int argc, char **argv) +{ + int c; + + initialize_main (&argc, &argv); + set_program_name (argv[0]); + setlocale (LC_ALL, ""); + bindtextdomain (PACKAGE, LOCALEDIR); + textdomain (PACKAGE); + hard_LC_COLLATE = hard_locale (LC_COLLATE); + + atexit (close_stdout); + + only_file_1 = true; + only_file_2 = true; + both = true; + + seen_unpairable = false; + issued_disorder_warning[0] = issued_disorder_warning[1] = false; + check_input_order = CHECK_ORDER_DEFAULT; + total_option = false; + + while ((c = getopt_long (argc, argv, "123z", long_options, NULL)) != -1) + switch (c) + { + case '1': + only_file_1 = false; + break; + + case '2': + only_file_2 = false; + break; + + case '3': + both = false; + break; + + case 'z': + delim = '\0'; + break; + + case NOCHECK_ORDER_OPTION: + check_input_order = CHECK_ORDER_DISABLED; + break; + + case CHECK_ORDER_OPTION: + check_input_order = CHECK_ORDER_ENABLED; + break; + + case OUTPUT_DELIMITER_OPTION: + if (col_sep_len && !STREQ (col_sep, optarg)) + die (EXIT_FAILURE, 0, _("multiple output delimiters specified")); + col_sep = optarg; + col_sep_len = *optarg ? strlen (optarg) : 1; + break; + + case TOTAL_OPTION: + total_option = true; + break; + + case_GETOPT_HELP_CHAR; + + case_GETOPT_VERSION_CHAR (PROGRAM_NAME, AUTHORS); + + default: + usage (EXIT_FAILURE); + } + + if (! col_sep_len) + col_sep_len = 1; + + if (argc - optind < 2) + { + if (argc <= optind) + error (0, 0, _("missing operand")); + else + error (0, 0, _("missing operand after %s"), quote (argv[argc - 1])); + usage (EXIT_FAILURE); + } + + if (2 < argc - optind) + { + error (0, 0, _("extra operand %s"), quote (argv[optind + 2])); + usage (EXIT_FAILURE); + } + + compare_files (argv + optind); + + if (issued_disorder_warning[0] || issued_disorder_warning[1]) + die (EXIT_FAILURE, 0, _("input is not in sorted order")); + else + return EXIT_SUCCESS; +} |