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         for (struct cdecl *i = decl; i; i = i->next) {
  50 retry:
  51                 rc = cdecl_explain(buf, bufsz, i);
  52                 if (rc >= bufsz) {
  53                         char *tmp;
  54
  55                         tmp = realloc(buf, rc + 1);
  56                         if (!tmp) {
  57                                 fprintf(stderr, "failed to allocate memory\n");
  58                                 goto out;
  59                         }
  60
  61                         buf = tmp;
  62                         bufsz = rc + 1;
  63                         goto retry;
  64                 }
  65
  66                 printf("%s\n", buf);
  67         }
  68 out:
  69         cdecl_free(decl);
  70         return 1;
  71 }
  72
  73 static int cmd_quit(char *cmd, char *arg)
  74 {
  75         return 0;
  76 }
  77
  78 static int cmd_help(char *cmd, char *arg);
  79
  80 static const struct command {
  81         char name[16];
  82         int (*func)(char *cmd, char *arg);
  83         const char *blurb;
  84 } commands[] = {
  85         { "explain", cmd_explain, "Explain a C declaration." },
  86         { "help",    cmd_help,    "Print this list of commands." },
  87         { "quit",    cmd_quit,    "Quit the program." },
  88         { "exit",    cmd_quit,    NULL }
  89 };
  90 static const size_t ncommands = sizeof commands / sizeof commands[0];
  91
  92 static int cmd_help(char *cmd, char *arg)
  93 {
  94         for (size_t i = 0; i < ncommands; i++) {
  95                 if (!commands[i].blurb)
  96                         continue;
  97
  98                 printf("%s -- %s\n", commands[i].name, commands[i].blurb);
  99         }
 100
 101         return 1;
 102 }
 103
 104 static int repl(void)
 105 {
 106         char *line;
 107         int ret;
 108
 109         print_version();
 110
 111         for (; (line = readline("> ")); free(line)) {
 112                 char *cmd = line + strspn(line, " \t");
 113                 char *arg = cmd  + strcspn(cmd, " \t");
 114
 115                 if (cmd[0] == '\0')
 116                         continue;
 117                 if (arg[0] != '\0')
 118                         *arg++ = '\0';
 119
 120                 for (size_t i = 0; i < ncommands; i++) {
 121                         if (strcmp(cmd, commands[i].name) != 0)
 122                                 continue;
 123
 124                         ret = commands[i].func(cmd, arg);
 125                         if (ret <= 0)
 126                                 goto out;
 127                         goto next;
 128                 }
 129
 130                 fprintf(stderr, "Undefined command: %s\n", cmd);
 131         next:
 132                 ;
 133         }
 134
 135         ret = 0;
 136 out:
 137         free(line);
 138         return ret;
 139 }
 140
 141 int main(int argc, char **argv)
 142 {
 143         int opt;
 144
 145         if (argc > 0)
 146                 progname = argv[0];
 147
 148         while ((opt = getopt_long(argc, argv, sopts, lopts, NULL)) != -1) {
 149                 switch (opt) {
 150                 case 'V':
 151                         print_version();
 152                         return EXIT_SUCCESS;
 153                 case 'H':
 154                         print_help();
 155                         return EXIT_SUCCESS;
 156                 default:
 157                         print_usage(stderr);
 158                         return EXIT_FAILURE;
 159                 }
 160         }
 161
 162         if (repl() != 0)
 163                 return EXIT_FAILURE;
 164
 165         return EXIT_SUCCESS;
 166 }