File: tcatl.c
   1 /*
   2 The MIT License (MIT)
   3 
   4 Copyright © 2020-2025 pacman64
   5 
   6 Permission is hereby granted, free of charge, to any person obtaining a copy of
   7 this software and associated documentation files (the “Software”), to deal
   8 in the Software without restriction, including without limitation the rights to
   9 use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
  10 of the Software, and to permit persons to whom the Software is furnished to do
  11 so, subject to the following conditions:
  12 
  13 The above copyright notice and this permission notice shall be included in all
  14 copies or substantial portions of the Software.
  15 
  16 THE SOFTWARE IS PROVIDED “AS IS”, WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  19 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  22 SOFTWARE.
  23 */
  24 
  25 /*
  26 You can build this command-line app by running
  27 
  28 cc -Wall -s -O3 -march=native -mtune=native -flto -o ./tcatl ./tcatl.c
  29 */
  30 
  31 #include <stdbool.h>
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35 #include <unistd.h>
  36 
  37 #ifdef _WIN32
  38 #include <fcntl.h>
  39 #include <windows.h>
  40 #endif
  41 
  42 #ifdef RED_ERRORS
  43 #define ERROR_STYLE "\x1b[38;2;204;0;0m"
  44 #ifdef __APPLE__
  45 #define ERROR_STYLE "\x1b[31m"
  46 #endif
  47 #define RESET_STYLE "\x1b[0m"
  48 #else
  49 #define ERROR_STYLE
  50 #define RESET_STYLE
  51 #endif
  52 
  53 #define ERROR_LINE(MSG) (ERROR_STYLE MSG RESET_STYLE "\n")
  54 
  55 #define BAD_ALLOC 2
  56 
  57 #ifndef IBUF_SIZE
  58 #define IBUF_SIZE (32 * 1024)
  59 #endif
  60 
  61 const char* info = ""
  62 "tcatl [filenames...]\n"
  63 "\n"
  64 "Title and Concatenate lines emits lines from all the named sources given,\n"
  65 "preceding each file's contents with its name, using an ANSI reverse style.\n"
  66 "\n"
  67 "The name `-` stands for the standard input. When no names are given, the\n"
  68 "standard input is used by default.\n"
  69 "";
  70 
  71 // slice is a growable region of bytes in memory
  72 typedef struct slice {
  73     // ptr is the starting place of the region
  74     unsigned char* ptr;
  75 
  76     // cap is how many bytes the memory region has available
  77     size_t cap;
  78 } slice;
  79 
  80 void handle_reader_faster(FILE* w, FILE* r) {
  81     unsigned char buf[IBUF_SIZE];
  82     unsigned char last = '\n';
  83 
  84     while (!feof(w)) {
  85         size_t len = fread(buf, sizeof(buf[0]), sizeof(buf), r);
  86         if (len < 1) {
  87             break;
  88         }
  89 
  90         fwrite(buf, 1, len, w);
  91         last = buf[len - 1];
  92     }
  93 
  94     if (last != '\n') {
  95         fputc('\n', w);
  96     }
  97 }
  98 
  99 void handle_reader(FILE* w, FILE* r, slice* line, bool live_lines) {
 100     if (!live_lines) {
 101         handle_reader_faster(w, r);
 102         return;
 103     }
 104 
 105     while (!feof(w)) {
 106         ssize_t len = getline((char**)&line->ptr, &line->cap, r);
 107         if (line->ptr == NULL) {
 108             fprintf(stderr, "\n");
 109             fprintf(stderr, ERROR_LINE("out of memory"));
 110             exit(BAD_ALLOC);
 111         }
 112 
 113         if (len < 0) {
 114             break;
 115         }
 116 
 117         fwrite(line->ptr, 1, len, w);
 118         const bool has_lf = len >= 1 && line->ptr[len - 1] == '\n';
 119         if (!has_lf) {
 120             fputc('\n', w);
 121         }
 122         fflush(w);
 123     }
 124 }
 125 
 126 // handle_file handles data from the filename given; returns false only when
 127 // the file can't be opened
 128 bool handle_file(FILE* w, const char* path, slice* line, bool live_lines) {
 129     fprintf(w, "\x1b[7m%s\x1b[0m\n", path);
 130 
 131     FILE* f = fopen(path, "rb");
 132     if (f == NULL) {
 133         fprintf(stderr, ERROR_LINE("can't open file named '%s'"), path);
 134         return false;
 135     }
 136 
 137     handle_reader(w, f, line, live_lines);
 138     fclose(f);
 139     return true;
 140 }
 141 
 142 // run returns the number of errors
 143 int run(char** args, size_t nargs, FILE* w, bool live_lines) {
 144     size_t dashes = 0;
 145     for (size_t i = 0; i < nargs; i++) {
 146         if (args[i][0] == '-' && args[i][1] == 0) {
 147             dashes++;
 148         }
 149     }
 150 
 151     if (dashes > 1) {
 152         const char* m = "can't use the standard input (dash) more than once";
 153         fprintf(stderr, ERROR_LINE("%s"), m);
 154         return 1;
 155     }
 156 
 157     slice line;
 158     line.ptr = NULL;
 159     line.cap = 0;
 160 
 161     if (live_lines) {
 162         line.cap = 32 * 1024;
 163         line.ptr = malloc(line.cap);
 164         if (line.ptr == NULL) {
 165             fprintf(stderr, ERROR_LINE("out of memory"));
 166             exit(BAD_ALLOC);
 167         }
 168     }
 169 
 170     size_t errors = 0;
 171     for (size_t i = 0; i < nargs && !feof(w); i++) {
 172         if (args[i][0] == '-' && args[i][1] == 0) {
 173             fputs("\x1b[7m-\x1b[0m\n", w);
 174             handle_reader(w, stdin, &line, live_lines);
 175             continue;
 176         }
 177 
 178         if (!handle_file(w, args[i], &line, live_lines)) {
 179             errors++;
 180         }
 181     }
 182 
 183     // use stdin when not given any filepaths
 184     if (nargs < 1) {
 185         fputs("\x1b[7m-\x1b[0m\n", w);
 186         handle_reader(w, stdin, &line, live_lines);
 187     }
 188 
 189     free(line.ptr);
 190     return errors;
 191 }
 192 
 193 int main(int argc, char** argv) {
 194 #ifdef _WIN32
 195     setmode(fileno(stdin), O_BINARY);
 196     // ensure output lines end in LF instead of CRLF on windows
 197     setmode(fileno(stdout), O_BINARY);
 198     setmode(fileno(stderr), O_BINARY);
 199 #endif
 200 
 201     if (argc > 1) {
 202         if (
 203             strcmp(argv[1], "-h") == 0 ||
 204             strcmp(argv[1], "-help") == 0 ||
 205             strcmp(argv[1], "--h") == 0 ||
 206             strcmp(argv[1], "--help") == 0
 207         ) {
 208             fprintf(stdout, "%s", info);
 209             return 0;
 210         }
 211     }
 212 
 213     size_t nargs = argc - 1;
 214     char** args = argv + 1;
 215     if (nargs > 0 && strcmp(args[0], "--") == 0) {
 216         nargs--;
 217         args++;
 218     }
 219 
 220     const bool live_lines = lseek(fileno(stdout), 0, SEEK_CUR) != 0;
 221     if (!live_lines) {
 222         setvbuf(stdout, NULL, _IOFBF, 0);
 223     }
 224     return run(args, nargs, stdout, live_lines) == 0 ? 0 : 1;
 225 }