src/cdecl99.c

   1 #include <config.h>
   2 #include <stdio.h>
   3 #include <stdlib.h>
   4 #include <string.h>
   5 #include <getopt.h>
   6 #include "readline.h"
   7 #include "cdecl.h"
   8
   9 static const char *progname = "cdecl99";
  10 static const char sopts[] = "VH";
  11 static const struct option lopts[] = {
  12         { "version", 0, NULL, 'V' },
  13         { "help",    0, NULL, 'H' },
  14         { 0 }
  15 };
  16
  17 static void print_version(void)
  18 {
  19         puts(PACKAGE_STRING);
  20         puts("Copyright (C) 2011 Nick Bowler.");
  21         puts("License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>.");
  22         puts("This is free software: you are free to change and redistribute it.");
  23         puts("There is NO WARRANTY, to the extent permitted by law.");
  24 }
  25
  26 static void print_usage(FILE *f)
  27 {
  28         fprintf(f, "Usage: %s [options]\n", progname);
  29 }
  30
  31 static void print_help(void)
  32 {
  33         print_usage(stdout);
  34         puts("Detailed help coming soon.");
  35 }
  36
  37 static int cmd_explain(char *cmd, char *arg)
  38 {
  39         static size_t bufsz;
  40         static char *buf;
  41
  42         struct cdecl *decl;
  43         size_t rc;
  44
  45         decl = cdecl_parse_decl(arg);
  46         if (!decl)
  47                 goto out;
  48
  49 retry:
  50         rc = cdecl_explain(buf, bufsz, decl);
  51         if (rc >= bufsz) {
  52                 char *tmp;
  53
  54                 tmp = realloc(buf, rc + 1);
  55                 if (!tmp) {
  56                         fprintf(stderr, "failed to allocate memory\n");
  57                         return 1;
  58                 }
  59
  60                 buf = tmp;
  61                 bufsz = rc + 1;
  62                 goto retry;
  63         }
  64
  65         printf("%s\n", buf);
  66 out:
  67         cdecl_free(decl);
  68         return 1;
  69 }
  70
  71 static int cmd_quit(char *cmd, char *arg)
  72 {
  73         return 0;
  74 }
  75
  76 static int cmd_help(char *cmd, char *arg);
  77
  78 static const struct command {
  79         char name[16];
  80         int (*func)(char *cmd, char *arg);
  81         const char *blurb;
  82 } commands[] = {
  83         { "explain", cmd_explain, "Explain a C declaration." },
  84         { "help",    cmd_help,    "Print this list of commands." },
  85         { "quit",    cmd_quit,    "Quit the program." },
  86         { "exit",    cmd_quit,    NULL }
  87 };
  88 static const size_t ncommands = sizeof commands / sizeof commands[0];
  89
  90 static int cmd_help(char *cmd, char *arg)
  91 {
  92         for (size_t i = 0; i < ncommands; i++) {
  93                 if (!commands[i].blurb)
  94                         continue;
  95
  96                 printf("%s -- %s\n", commands[i].name, commands[i].blurb);
  97         }
  98
  99         return 1;
 100 }
 101
 102 static int repl(void)
 103 {
 104         char *line;
 105         int ret;
 106
 107         print_version();
 108
 109         for (; (line = readline("> ")); free(line)) {
 110                 char *cmd = line + strspn(line, " \t");
 111                 char *arg = cmd  + strcspn(cmd, " \t");
 112
 113                 if (cmd[0] == '\0')
 114                         continue;
 115                 if (arg[0] != '\0')
 116                         *arg++ = '\0';
 117
 118                 for (size_t i = 0; i < ncommands; i++) {
 119                         if (strcmp(cmd, commands[i].name) != 0)
 120                                 continue;
 121
 122                         ret = commands[i].func(cmd, arg);
 123                         if (ret <= 0)
 124                                 goto out;
 125                         goto next;
 126                 }
 127
 128                 fprintf(stderr, "Undefined command: %s\n", cmd);
 129         next:
 130                 ;
 131         }
 132
 133         ret = 0;
 134 out:
 135         free(line);
 136         return ret;
 137 }
 138
 139 int main(int argc, char **argv)
 140 {
 141         int opt;
 142
 143         if (argc > 0)
 144                 progname = argv[0];
 145
 146         while ((opt = getopt_long(argc, argv, sopts, lopts, NULL)) != -1) {
 147                 switch (opt) {
 148                 case 'V':
 149                         print_version();
 150                         return EXIT_SUCCESS;
 151                 case 'H':
 152                         print_help();
 153                         return EXIT_SUCCESS;
 154                 default:
 155                         print_usage(stderr);
 156                         return EXIT_FAILURE;
 157                 }
 158         }
 159
 160         if (repl() != 0)
 161                 return EXIT_FAILURE;
 162
 163         return EXIT_SUCCESS;
 164 }