fuse_opt.c
/*
FUSE: Filesystem in Userspace
Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu>
Implementation of option parsing routines (dealing with `struct
fuse_args`).
This program can be distributed under the terms of the GNU LGPLv2.
See the file COPYING.LIB
*/
#include "config.h"
#include "fuse_opt.h"
#include "fuse_misc.h"
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
struct fuse_opt_context {
void *data;
const struct fuse_opt *opt;
fuse_opt_proc_t proc;
int argctr;
int argc;
char **argv;
struct fuse_args outargs;
char *opts;
int nonopt;
};
void fuse_opt_free_args(struct fuse_args *args)
{
if (args) {
if (args->argv && args->allocated) {
int i;
for (i = 0; i < args->argc; i++)
free(args->argv[i]);
free(args->argv);
}
args->argc = 0;
args->argv = NULL;
args->allocated = 0;
}
}
static int alloc_failed(void)
{
fprintf(stderr, "fuse: memory allocation failed\n");
return -1;
}
int fuse_opt_add_arg(struct fuse_args *args, const char *arg)
{
char **newargv;
char *newarg;
assert(!args->argv || args->allocated);
newarg = strdup(arg);
if (!newarg)
return alloc_failed();
newargv = realloc(args->argv, (args->argc + 2) * sizeof(char *));
if (!newargv) {
free(newarg);
return alloc_failed();
}
args->argv = newargv;
args->allocated = 1;
args->argv[args->argc++] = newarg;
args->argv[args->argc] = NULL;
return 0;
}
static int fuse_opt_insert_arg_common(struct fuse_args *args, int pos,
const char *arg)
{
assert(pos <= args->argc);
if (fuse_opt_add_arg(args, arg) == -1)
return -1;
if (pos != args->argc - 1) {
char *newarg = args->argv[args->argc - 1];
memmove(&args->argv[pos + 1], &args->argv[pos],
sizeof(char *) * (args->argc - pos - 1));
args->argv[pos] = newarg;
}
return 0;
}
int fuse_opt_insert_arg(struct fuse_args *args, int pos, const char *arg)
{
return fuse_opt_insert_arg_common(args, pos, arg);
}
static int next_arg(struct fuse_opt_context *ctx, const char *opt)
{
if (ctx->argctr + 1 >= ctx->argc) {
fprintf(stderr, "fuse: missing argument after `%s'\n", opt);
return -1;
}
ctx->argctr++;
return 0;
}
static int add_arg(struct fuse_opt_context *ctx, const char *arg)
{
return fuse_opt_add_arg(&ctx->outargs, arg);
}
static int add_opt_common(char **opts, const char *opt, int esc)
{
unsigned oldlen = *opts ? strlen(*opts) : 0;
char *d = realloc(*opts, oldlen + 1 + strlen(opt) * 2 + 1);
if (!d)
return alloc_failed();
*opts = d;
if (oldlen) {
d += oldlen;
*d++ = ',';
}
for (; *opt; opt++) {
if (esc && (*opt == ',' || *opt == '\\'))
*d++ = '\\';
*d++ = *opt;
}
*d = '\0';
return 0;
}
int fuse_opt_add_opt(char **opts, const char *opt)
{
return add_opt_common(opts, opt, 0);
}
int fuse_opt_add_opt_escaped(char **opts, const char *opt)
{
return add_opt_common(opts, opt, 1);
}
static int add_opt(struct fuse_opt_context *ctx, const char *opt)
{
return add_opt_common(&ctx->opts, opt, 1);
}
static int call_proc(struct fuse_opt_context *ctx, const char *arg, int key,
int iso)
{
if (key == FUSE_OPT_KEY_DISCARD)
return 0;
if (key != FUSE_OPT_KEY_KEEP && ctx->proc) {
int res = ctx->proc(ctx->data, arg, key, &ctx->outargs);
if (res == -1 || !res)
return res;
}
if (iso)
return add_opt(ctx, arg);
else
return add_arg(ctx, arg);
}
static int match_template(const char *t, const char *arg, unsigned *sepp)
{
int arglen = strlen(arg);
const char *sep = strchr(t, '=');
sep = sep ? sep : strchr(t, ' ');
if (sep && (!sep[1] || sep[1] == '%')) {
int tlen = sep - t;
if (sep[0] == '=')
tlen ++;
if (arglen >= tlen && strncmp(arg, t, tlen) == 0) {
*sepp = sep - t;
return 1;
}
}
if (strcmp(t, arg) == 0) {
*sepp = 0;
return 1;
}
return 0;
}
static const struct fuse_opt *find_opt(const struct fuse_opt *opt,
const char *arg, unsigned *sepp)
{
for (; opt && opt->templ; opt++)
if (match_template(opt->templ, arg, sepp))
return opt;
return NULL;
}
int fuse_opt_match(const struct fuse_opt *opts, const char *opt)
{
unsigned dummy;
return find_opt(opts, opt, &dummy) ? 1 : 0;
}
static int process_opt_param(void *var, const char *format, const char *param,
const char *arg)
{
assert(format[0] == '%');
if (format[1] == 's') {
char **s = var;
char *copy = strdup(param);
if (!copy)
return alloc_failed();
free(*s);
*s = copy;
} else {
if (sscanf(param, format, var) != 1) {
fprintf(stderr, "fuse: invalid parameter in option `%s'\n", arg);
return -1;
}
}
return 0;
}
static int process_opt(struct fuse_opt_context *ctx,
const struct fuse_opt *opt, unsigned sep,
const char *arg, int iso)
{
if (opt->offset == -1U) {
if (call_proc(ctx, arg, opt->value, iso) == -1)
return -1;
} else {
void *var = ctx->data + opt->offset;
if (sep && opt->templ[sep + 1]) {
const char *param = arg + sep;
if (opt->templ[sep] == '=')
param ++;
if (process_opt_param(var, opt->templ + sep + 1,
param, arg) == -1)
return -1;
} else
*(int *)var = opt->value;
}
return 0;
}
static int process_opt_sep_arg(struct fuse_opt_context *ctx,
const struct fuse_opt *opt, unsigned sep,
const char *arg, int iso)
{
int res;
char *newarg;
char *param;
if (next_arg(ctx, arg) == -1)
return -1;
param = ctx->argv[ctx->argctr];
newarg = malloc(sep + strlen(param) + 1);
if (!newarg)
return alloc_failed();
memcpy(newarg, arg, sep);
strcpy(newarg + sep, param);
res = process_opt(ctx, opt, sep, newarg, iso);
free(newarg);
return res;
}
static int process_gopt(struct fuse_opt_context *ctx, const char *arg, int iso)
{
unsigned sep;
const struct fuse_opt *opt = find_opt(ctx->opt, arg, &sep);
if (opt) {
for (; opt; opt = find_opt(opt + 1, arg, &sep)) {
int res;
if (sep && opt->templ[sep] == ' ' && !arg[sep])
res = process_opt_sep_arg(ctx, opt, sep, arg,
iso);
else
res = process_opt(ctx, opt, sep, arg, iso);
if (res == -1)
return -1;
}
return 0;
} else
return call_proc(ctx, arg, FUSE_OPT_KEY_OPT, iso);
}
static int process_real_option_group(struct fuse_opt_context *ctx, char *opts)
{
char *s = opts;
char *d = s;
int end = 0;
while (!end) {
if (*s == '\0')
end = 1;
if (*s == ',' || end) {
int res;
*d = '\0';
res = process_gopt(ctx, opts, 1);
if (res == -1)
return -1;
d = opts;
} else {
if (s[0] == '\\' && s[1] != '\0') {
s++;
if (s[0] >= '0' && s[0] <= '3' &&
s[1] >= '0' && s[1] <= '7' &&
s[2] >= '0' && s[2] <= '7') {
*d++ = (s[0] - '0') * 0100 +
(s[1] - '0') * 0010 +
(s[2] - '0');
s += 2;
} else {
*d++ = *s;
}
} else {
*d++ = *s;
}
}
s++;
}
return 0;
}
static int process_option_group(struct fuse_opt_context *ctx, const char *opts)
{
int res;
char *copy = strdup(opts);
if (!copy) {
fprintf(stderr, "fuse: memory allocation failed\n");
return -1;
}
res = process_real_option_group(ctx, copy);
free(copy);
return res;
}
static int process_one(struct fuse_opt_context *ctx, const char *arg)
{
if (ctx->nonopt || arg[0] != '-')
return call_proc(ctx, arg, FUSE_OPT_KEY_NONOPT, 0);
else if (arg[1] == 'o') {
if (arg[2])
return process_option_group(ctx, arg + 2);
else {
if (next_arg(ctx, arg) == -1)
return -1;
return process_option_group(ctx,
ctx->argv[ctx->argctr]);
}
} else if (arg[1] == '-' && !arg[2]) {
if (add_arg(ctx, arg) == -1)
return -1;
ctx->nonopt = ctx->outargs.argc;
return 0;
} else
return process_gopt(ctx, arg, 0);
}
static int opt_parse(struct fuse_opt_context *ctx)
{
if (ctx->argc) {
if (add_arg(ctx, ctx->argv[0]) == -1)
return -1;
}
for (ctx->argctr = 1; ctx->argctr < ctx->argc; ctx->argctr++)
if (process_one(ctx, ctx->argv[ctx->argctr]) == -1)
return -1;
if (ctx->opts) {
if (fuse_opt_insert_arg(&ctx->outargs, 1, "-o") == -1 ||
fuse_opt_insert_arg(&ctx->outargs, 2, ctx->opts) == -1)
return -1;
}
/* If option separator ("--") is the last argument, remove it */
if (ctx->nonopt && ctx->nonopt == ctx->outargs.argc &&
strcmp(ctx->outargs.argv[ctx->outargs.argc - 1], "--") == 0) {
free(ctx->outargs.argv[ctx->outargs.argc - 1]);
ctx->outargs.argv[--ctx->outargs.argc] = NULL;
}
return 0;
}
int fuse_opt_parse(struct fuse_args *args, void *data,
const struct fuse_opt opts[], fuse_opt_proc_t proc)
{
int res;
struct fuse_opt_context ctx = {
.data = data,
.opt = opts,
.proc = proc,
};
if (!args || !args->argv || !args->argc)
return 0;
ctx.argc = args->argc;
ctx.argv = args->argv;
res = opt_parse(&ctx);
if (res != -1) {
struct fuse_args tmp = *args;
*args = ctx.outargs;
ctx.outargs = tmp;
}
free(ctx.opts);
fuse_opt_free_args(&ctx.outargs);
return res;
}
fuse_opt_add_opt_escaped
int fuse_opt_add_opt_escaped(char **opts, const char *opt)
Definition: fuse_opt.c:143
fuse_args::argc
int argc
Definition: fuse_opt.h:111
fuse_opt::offset
unsigned long offset
Definition: fuse_opt.h:85
fuse_opt_parse
int fuse_opt_parse(struct fuse_args *args, void *data, const struct fuse_opt opts[], fuse_opt_proc_t proc)
Definition: fuse_opt.c:397
fuse_args::allocated
int allocated
Definition: fuse_opt.h:117
fuse_opt::value
int value
Definition: fuse_opt.h:91
fuse_opt_match
int fuse_opt_match(const struct fuse_opt opts[], const char *opt)
fuse_opt::templ
const char * templ
Definition: fuse_opt.h:79
fuse_opt_add_arg
int fuse_opt_add_arg(struct fuse_args *args, const char *arg)
Definition: fuse_opt.c:54
FUSE_OPT_KEY_DISCARD
#define FUSE_OPT_KEY_DISCARD
Definition: fuse_opt.h:153
FUSE_OPT_KEY_OPT
#define FUSE_OPT_KEY_OPT
Definition: fuse_opt.h:129
fuse_opt_free_args
void fuse_opt_free_args(struct fuse_args *args)
Definition: fuse_opt.c:33
fuse_opt.h
FUSE_OPT_KEY_KEEP
#define FUSE_OPT_KEY_KEEP
Definition: fuse_opt.h:145
fuse_opt_add_opt
int fuse_opt_add_opt(char **opts, const char *opt)
Definition: fuse_opt.c:138
fuse_opt_insert_arg
int fuse_opt_insert_arg(struct fuse_args *args, int pos, const char *arg)
Definition: fuse_opt.c:94
FUSE_OPT_KEY_NONOPT
#define FUSE_OPT_KEY_NONOPT
Definition: fuse_opt.h:137
fuse_args::argv
char ** argv
Definition: fuse_opt.h:114
fuse_opt
Definition: fuse_opt.h:77
fuse_args
Definition: fuse_opt.h:109
fuse_opt_proc_t
int(* fuse_opt_proc_t)(void *data, const char *arg, int key, struct fuse_args *outargs)
Definition: fuse_opt.h:180