/* $OpenBSD: fuse_opt.c,v 1.25 2017/12/15 16:40:33 jca Exp $ */ /* * Copyright (c) 2013 Sylvestre Gallon * Copyright (c) 2013 Stefan Sperling * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. */ #include #include #include #include #include "debug.h" #include "fuse_opt.h" #include "fuse_private.h" #define IFUSE_OPT_DISCARD 0 #define IFUSE_OPT_KEEP 1 #define IFUSE_OPT_NEED_ANOTHER_ARG 2 static void free_argv(char **argv, int argc) { int i; for (i = 0; i < argc; i++) free(argv[i]); free(argv); } static int alloc_argv(struct fuse_args *args) { char **argv; int i; assert(!args->allocated); argv = calloc(args->argc, sizeof(*argv)); if (argv == NULL) return (-1); if (args->argv) { for (i = 0; i < args->argc; i++) { argv[i] = strdup(args->argv[i]); if (argv[i] == NULL) { free_argv(argv, i + 1); return (-1); } } } args->allocated = 1; args->argv = argv; return (0); } /* * Returns the number of characters that matched for bounds checking later. */ static size_t match_opt(const char *templ, const char *opt) { size_t sep, len; len = strlen(templ); sep = strcspn(templ, "="); if (sep == len) sep = strcspn(templ, " "); /* key=, key=%, "-k ", -k % */ if (sep < len && (templ[sep + 1] == '\0' || templ[sep + 1] == '%')) { if (strncmp(opt, templ, sep) == 0) return (sep); else return (0); } if (strcmp(opt, templ) == 0) return (len); return (0); } static int add_opt(char **opts, const char *opt) { char *new_opts; if (*opts == NULL) { *opts = strdup(opt); if (*opts == NULL) return (-1); return (0); } if (asprintf(&new_opts, "%s,%s", *opts, opt) == -1) return (-1); free(*opts); *opts = new_opts; return (0); } int fuse_opt_add_opt(char **opts, const char *opt) { int ret; if (opt == NULL || opt[0] == '\0') return (-1); ret = add_opt(opts, opt); return (ret); } int fuse_opt_add_opt_escaped(char **opts, const char *opt) { size_t size = 0, escaped = 0; const char *s = opt; char *escaped_opt, *p; int ret; if (opt == NULL || opt[0] == '\0') return (-1); while (*s) { /* malloc(size + escaped) overflow check */ if (size >= (SIZE_MAX / 2)) return (-1); if (*s == ',' || *s == '\\') escaped++; s++; size++; } size++; /* trailing NUL */ if (escaped > 0) { escaped_opt = malloc(size + escaped); if (escaped_opt == NULL) return (-1); s = opt; p = escaped_opt; while (*s) { switch (*s) { case ',': case '\\': *p++ = '\\'; /* FALLTHROUGH */ default: *p++ = *s++; } } *p = '\0'; } else { escaped_opt = strdup(opt); if (escaped_opt == NULL) return (-1); } ret = add_opt(opts, escaped_opt); free(escaped_opt); return (ret); } int fuse_opt_add_arg(struct fuse_args *args, const char *name) { return (fuse_opt_insert_arg(args, args->argc, name)); } DEF(fuse_opt_add_arg); static int parse_opt(const struct fuse_opt *o, const char *opt, void *data, fuse_opt_proc_t f, struct fuse_args *arg) { const char *val; int keyval, ret, found; size_t sep; keyval = 0; found = 0; for(; o != NULL && o->templ; o++) { sep = match_opt(o->templ, opt); if (sep == 0) continue; found = 1; val = opt; /* check key=value or -p n */ if (o->templ[sep] == '=') { keyval = 1; val = &opt[sep + 1]; } else if (o->templ[sep] == ' ') { keyval = 1; if (sep == strlen(opt)) { /* ask for next arg to be included */ return (IFUSE_OPT_NEED_ANOTHER_ARG); } else if (strchr(o->templ, '%') != NULL) { val = &opt[sep]; } } if (o->val == FUSE_OPT_KEY_DISCARD) ret = IFUSE_OPT_DISCARD; else if (o->val == FUSE_OPT_KEY_KEEP) ret = IFUSE_OPT_KEEP; else if (FUSE_OPT_IS_OPT_KEY(o)) { if (f == NULL) return (IFUSE_OPT_KEEP); ret = f(data, val, o->val, arg); } else if (data == NULL) { return (-1); } else if (strchr(o->templ, '%') == NULL) { *((int *)(data + o->off)) = o->val; ret = IFUSE_OPT_DISCARD; } else if (strstr(o->templ, "%s") != NULL) { *((char **)(data + o->off)) = strdup(val); ret = IFUSE_OPT_DISCARD; } else { /* All other templates, let sscanf deal with them. */ if (sscanf(opt, o->templ, data + o->off) != 1) { fprintf(stderr, "fuse: Invalid value %s for " "option %s\n", val, o->templ); return (-1); } ret = IFUSE_OPT_DISCARD; } } if (found) return (ret); if (f != NULL) return f(data, opt, FUSE_OPT_KEY_OPT, arg); return (IFUSE_OPT_KEEP); } /* * this code is not very sexy but we are forced to follow * the fuse api. * * when f() returns 1 we need to keep the arg * when f() returns 0 we need to discard the arg */ int fuse_opt_parse(struct fuse_args *args, void *data, const struct fuse_opt *opt, fuse_opt_proc_t f) { struct fuse_args outargs; const char *arg, *ap; char *optlist, *tofree; int ret; int i; if (!args || !args->argc || !args->argv) return (0); bzero(&outargs, sizeof(outargs)); fuse_opt_add_arg(&outargs, args->argv[0]); for (i = 1; i < args->argc; i++) { arg = args->argv[i]; ret = 0; /* not - and not -- */ if (arg[0] != '-') { if (f == NULL) ret = IFUSE_OPT_KEEP; else ret = f(data, arg, FUSE_OPT_KEY_NONOPT, &outargs); if (ret == IFUSE_OPT_KEEP) fuse_opt_add_arg(&outargs, arg); if (ret == -1) goto err; } else if (arg[1] == 'o') { if (arg[2]) arg += 2; /* -ofoo,bar */ else { if (++i >= args->argc) goto err; arg = args->argv[i]; } tofree = optlist = strdup(arg); if (optlist == NULL) goto err; while ((ap = strsep(&optlist, ",")) != NULL && ret != -1) { ret = parse_opt(opt, ap, data, f, &outargs); if (ret == IFUSE_OPT_KEEP) { fuse_opt_add_arg(&outargs, "-o"); fuse_opt_add_arg(&outargs, ap); } } free(tofree); if (ret == -1) goto err; } else { ret = parse_opt(opt, arg, data, f, &outargs); if (ret == IFUSE_OPT_KEEP) fuse_opt_add_arg(&outargs, arg); else if (ret == IFUSE_OPT_NEED_ANOTHER_ARG) { /* arg needs a value */ if (++i >= args->argc) { fprintf(stderr, "fuse: missing argument after %s\n", arg); goto err; } if (asprintf(&tofree, "%s%s", arg, args->argv[i]) == -1) goto err; ret = parse_opt(opt, tofree, data, f, &outargs); if (ret == IFUSE_OPT_KEEP) fuse_opt_add_arg(&outargs, tofree); free(tofree); } if (ret == -1) goto err; } } ret = 0; err: /* Update args */ fuse_opt_free_args(args); args->allocated = outargs.allocated; args->argc = outargs.argc; args->argv = outargs.argv; if (ret != 0) ret = -1; return (ret); } DEF(fuse_opt_parse); int fuse_opt_insert_arg(struct fuse_args *args, int p, const char *name) { char **av; char *this_arg, *next_arg; int i; if (name == NULL) return (-1); if (!args->allocated && alloc_argv(args)) return (-1); if (p < 0 || p > args->argc) return (-1); av = reallocarray(args->argv, args->argc + 2, sizeof(*av)); if (av == NULL) return (-1); this_arg = strdup(name); if (this_arg == NULL) { free(av); return (-1); } args->argc++; args->argv = av; args->argv[args->argc] = NULL; for (i = p; i < args->argc; i++) { next_arg = args->argv[i]; args->argv[i] = this_arg; this_arg = next_arg; } return (0); } DEF(fuse_opt_insert_arg); void fuse_opt_free_args(struct fuse_args *args) { if (!args->allocated) return; free_argv(args->argv, args->argc); args->argv = 0; args->argc = 0; args->allocated = 0; } DEF(fuse_opt_free_args); int fuse_opt_match(const struct fuse_opt *opts, const char *opt) { const struct fuse_opt *this_opt = opts; if (opt == NULL || opt[0] == '\0') return (0); while (this_opt->templ) { if (match_opt(this_opt->templ, opt)) return (1); this_opt++; } return (0); } DEF(fuse_opt_match);