/*
* Command line utility for making sense of C declarations.
* Copyright © 2011 Nick Bowler
*
* 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 .
*/
#include
#include
#include
#include
#include
#include
#include
#include "readline.h"
#include "cdecl.h"
static const char *progname = "cdecl99";
static const char sopts[] = "qbif:e:VH";
static const struct option lopts[] = {
{ "quiet", 0, NULL, 'q' },
{ "batch", 0, NULL, 'b' },
{ "interactive", 0, NULL, 'i' },
{ "file", 1, NULL, 'f' },
{ "execute", 1, NULL, 'e' },
{ "version", 0, NULL, 'V' },
{ "help", 0, NULL, 'H' },
{ 0 }
};
static void print_version(void)
{
puts(PACKAGE_STRING);
puts("Copyright (C) 2011 Nick Bowler.");
puts("License GPLv3+: GNU GPL version 3 or later .");
puts("This is free software: you are free to change and redistribute it.");
puts("There is NO WARRANTY, to the extent permitted by law.");
}
static void print_usage(FILE *f)
{
fprintf(f, "Usage: %s [options]\n", progname);
}
static void print_help(void)
{
print_usage(stdout);
puts("Detailed help coming soon.");
}
/*
* Format a declaration according to the given function and return a pointer
* to the formatted string. The returned pointer remains valid until the
* next call, after which it must not be re-used.
*
* Returns NULL on failure.
*/
static const char *
do_format(size_t func(char *, size_t, struct cdecl *), struct cdecl *decl)
{
static size_t bufsz;
static char *buf;
size_t rc;
retry:
rc = func(buf, bufsz, decl);
if (rc >= bufsz) {
char *tmp;
tmp = realloc(buf, rc + 1);
if (!tmp) {
fprintf(stderr, "failed to allocate memory\n");
return NULL;
}
buf = tmp;
bufsz = rc + 1;
goto retry;
}
return buf;
}
static int cmd_explain(const char *cmd, const char *arg)
{
struct cdecl *decl;
const char *str;
int ret = -1;
decl = cdecl_parse_decl(arg);
if (!decl)
goto out;
for (struct cdecl *i = decl; i; i = i->next) {
str = do_format(cdecl_explain, i);
if (!str)
goto out;
printf("%s\n", str);
}
ret = 1;
out:
cdecl_free(decl);
return ret;
}
static int cmd_simplify(const char *cmd, const char *arg)
{
struct cdecl *decl;
const char *str;
int ret = -1;
decl = cdecl_parse_decl(arg);
if (!decl)
goto out;
for (struct cdecl *i = decl; i; i = i->next) {
struct cdecl_declspec *s = i->specifiers;
if (i != decl) {
i->specifiers = NULL;
printf(", ");
}
str = do_format(cdecl_declare, i);
i->specifiers = s;
if (!str)
goto out;
printf("%s", str);
}
putchar('\n');
ret = 1;
out:
cdecl_free(decl);
return ret;
}
static int cmd_quit(const char *cmd, const char *arg)
{
return 0;
}
static int cmd_help(const char *cmd, const char *arg);
static const struct command {
char name[16];
int (*func)(const char *cmd, const char *arg);
const char *blurb;
} commands[] = {
{ "explain", cmd_explain, "Explain a C declaration." },
{ "simplify", cmd_simplify, "Simplify a C declaration." },
{ "help", cmd_help, "Print this list of commands." },
{ "quit", cmd_quit, "Quit the program." },
{ "exit", cmd_quit, NULL }
};
static const size_t ncommands = sizeof commands / sizeof commands[0];
static int cmd_help(const char *cmd, const char *arg)
{
for (size_t i = 0; i < ncommands; i++) {
if (!commands[i].blurb)
continue;
printf("%s -- %s\n", commands[i].name, commands[i].blurb);
}
return 1;
}
/*
* Ensure that the first n characters of str equal the entire (null-terminated)
* string cmd.
*/
static int cmd_cmp(const char *str, const char *cmd, size_t n)
{
size_t cmdlen = strlen(cmd);
if (n < cmdlen)
return -1;
if (n > cmdlen)
return 1;
return memcmp(str, cmd, n);
}
static int run_command(const char *line)
{
const char *cmd = line + strspn(line, " \t");
const char *arg = cmd + strcspn(cmd, " \t");
if (cmd[0] == '\0')
return 1;
for (size_t i = 0; i < ncommands; i++) {
if (cmd_cmp(cmd, commands[i].name, arg-cmd) != 0)
continue;
return commands[i].func(cmd, arg);
}
fprintf(stderr, "Undefined command: %.*s\n", (int)(arg-cmd), cmd);
return -1;
}
static int repl(void)
{
char *line;
for (; (line = readline("> ")); free(line)) {
if (!run_command(line))
break;
}
free(line);
return 0;
}
static int repl_cmdline(int argc, char **argv)
{
int opt, rc, ret = 0;
optind = 1;
while ((opt = getopt_long(argc, argv, sopts, lopts, NULL)) != -1) {
if (opt != 'e')
continue;
rc = run_command(optarg);
if (rc < 0)
ret = -1;
else if (rc == 0)
break;
}
return ret;
}
static int repl_noninteractive(void)
{
int rc, ret = 0, saved_errno;
char *line = NULL;
size_t n;
while (getline(&line, &n, stdin) >= 0) {
char *c = strchr(line, '\n');
if (c)
*c = '\0';
rc = run_command(line);
if (rc < 0)
ret = -1;
else if (rc == 0)
break;
}
saved_errno = errno;
free(line);
if (ferror(stdin)) {
errno = saved_errno;
perror("read error");
return -1;
}
return ret;
}
int main(int argc, char **argv)
{
bool show_intro = true, interactive = true, execute = false;
const char *filename = NULL;
int opt, rc;
if (argc > 0)
progname = argv[0];
while ((opt = getopt_long(argc, argv, sopts, lopts, NULL)) != -1) {
switch (opt) {
case 'q':
show_intro = false;
break;
case 'b':
interactive = false;
break;
case 'i':
interactive = true;
break;
case 'f':
filename = optarg;
break;
case 'e':
execute = true;
break;
case 'V':
print_version();
return EXIT_SUCCESS;
case 'H':
print_help();
return EXIT_SUCCESS;
default:
print_usage(stderr);
return EXIT_FAILURE;
}
}
/* --filename and --execute imply --batch. */
if (filename || execute)
interactive = false;
/* --batch implies --quiet */
if (interactive && show_intro)
print_version();
/* --execute supersedes --filename */
if (filename && !execute) {
if (!freopen(filename, "r", stdin)) {
perror(filename);
return EXIT_FAILURE;
}
}
if (interactive)
rc = repl();
else if (execute)
rc = repl_cmdline(argc, argv);
else
rc = repl_noninteractive();
if (rc != 0)
return EXIT_FAILURE;
return EXIT_SUCCESS;
}