LXR busybox/coreutils/paste.c

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * paste.c - implementation of the posix paste command
   4 *
   5 * Written by Maxime Coste <mawww@kakoune.org>
   6 *
   7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8 */
   9//config:config PASTE
  10//config:       bool "paste (4.9 kb)"
  11//config:       default y
  12//config:       help
  13//config:       paste is used to paste lines of different files together
  14//config:       and write the result to stdout
  15
  16//applet:IF_PASTE(APPLET_NOEXEC(paste, paste, BB_DIR_USR_BIN, BB_SUID_DROP, paste))
  17
  18//kbuild:lib-$(CONFIG_PASTE) += paste.o
  19
  20//usage:#define paste_trivial_usage
  21//usage:       "[OPTIONS] [FILE]..."
  22//usage:#define paste_full_usage "\n\n"
  23//usage:       "Paste lines from each input file, separated with tab\n"
  24//usage:     "\n        -d LIST Use delimiters from LIST, not tab"
  25//usage:     "\n        -s      Serial: one file at a time"
  26//usage:
  27//usage:#define paste_example_usage
  28//usage:       "# write out directory in four columns\n"
  29//usage:       "$ ls | paste - - - -\n"
  30//usage:       "# combine pairs of lines from a file into single lines\n"
  31//usage:       "$ paste -s -d '\\t\\n' file\n"
  32
  33#include "libbb.h"
  34
  35static void paste_files(FILE** files, int file_cnt, char* delims, int del_cnt)
  36{
  37        char *line;
  38        char delim;
  39        int active_files = file_cnt;
  40        int i;
  41
  42        while (active_files > 0) {
  43                int del_idx = 0;
  44
  45                for (i = 0; i < file_cnt; ++i) {
  46                        if (files[i] == NULL)
  47                                continue;
  48
  49                        line = xmalloc_fgetline(files[i]);
  50                        if (!line) {
  51                                fclose_if_not_stdin(files[i]);
  52                                files[i] = NULL;
  53                                --active_files;
  54                                continue;
  55                        }
  56                        fputs(line, stdout);
  57                        free(line);
  58                        delim = '\n';
  59                        if (i != file_cnt - 1) {
  60                                delim = delims[del_idx++];
  61                                if (del_idx == del_cnt)
  62                                        del_idx = 0;
  63                        }
  64                        if (delim != '\0')
  65                                fputc(delim, stdout);
  66                }
  67        }
  68}
  69
  70static void paste_files_separate(FILE** files, char* delims, int del_cnt)
  71{
  72        char *line, *next_line;
  73        char delim;
  74        int i;
  75
  76        for (i = 0; files[i]; ++i) {
  77                int del_idx = 0;
  78
  79                line = NULL;
  80                while ((next_line = xmalloc_fgetline(files[i])) != NULL) {
  81                        if (line) {
  82                                fputs(line, stdout);
  83                                free(line);
  84                                delim = delims[del_idx++];
  85                                if (del_idx == del_cnt)
  86                                        del_idx = 0;
  87                                if (delim != '\0')
  88                                        fputc(delim, stdout);
  89                        }
  90                        line = next_line;
  91                }
  92                if (line) {
  93                        /* coreutils adds \n even if this is a final line
  94                         * of the last file and it was not \n-terminated.
  95                         */
  96                        printf("%s\n", line);
  97                        free(line);
  98                }
  99                fclose_if_not_stdin(files[i]);
 100        }
 101}
 102
 103#define PASTE_OPT_DELIMITERS (1 << 0)
 104#define PASTE_OPT_SEPARATE   (1 << 1)
 105
 106int paste_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 107int paste_main(int argc UNUSED_PARAM, char **argv)
 108{
 109        char *delims = (char*)"\t";
 110        int del_cnt = 1;
 111        unsigned opt;
 112        int i;
 113
 114        opt = getopt32(argv, "d:s", &delims);
 115        argv += optind;
 116
 117        if (opt & PASTE_OPT_DELIMITERS) {
 118                if (!delims[0])
 119                        bb_error_msg_and_die("-d '' is not supported");
 120                /* unknown mappings are not changed: "\z" -> '\\' 'z' */
 121                /* trailing backslash, if any, is preserved */
 122                del_cnt = strcpy_and_process_escape_sequences(delims, delims) - delims;
 123                /* note: handle NUL properly (do not stop at it!): try -d'\t\0\t' */
 124        }
 125
 126        if (!argv[0])
 127                (--argv)[0] = (char*) "-";
 128        for (i = 0; argv[i]; ++i) {
 129                argv[i] = (void*) fopen_or_warn_stdin(argv[i]);
 130                if (!argv[i])
 131                        xfunc_die();
 132        }
 133
 134        if (opt & PASTE_OPT_SEPARATE)
 135                paste_files_separate((FILE**)argv, delims, del_cnt);
 136        else
 137                paste_files((FILE**)argv, i, delims, del_cnt);
 138
 139        fflush_stdout_and_exit(0);
 140}
 141