| /* vi: set sw=4 ts=4 : |
| * args.c - Command line argument parsing. |
| * |
| * Copyright 2006 Rob Landley <rob@landley.net> |
| */ |
| |
| #include "toys.h" |
| |
| // Design goals: |
| // Don't use getopt() |
| // Don't permute original arguments. |
| // handle --long gracefully "(noshort)a(along)b(blong1)(blong2)" |
| // After each argument: |
| // Note that pointer and long are always the same size, even on 64 bit. |
| // : plus a string argument, keep most recent if more than one |
| // * plus a string argument, appended to a list |
| // # plus a signed long argument (TODO: Bounds checking?) |
| // @ plus an occurrence counter (which is a long) |
| // (longopt) |
| // | this is required. If more than one marked, only one required. |
| // ^ Stop parsing after encountering this argument |
| // |
| // These modify other option letters (previously seen in string): |
| // +X enabling this enables X (switch on) |
| // ~X enabling this disables X (switch off) |
| // !X die with error if X already set (x!x die if x supplied twice) |
| // [yz] needs at least one of y or z. |
| // at the beginning: |
| // ^ stop at first nonoption argument |
| // <0 at least # leftover arguments needed (default 0) |
| // >9 at most # leftover arguments needed (default MAX_INT) |
| // ? don't show_usage() on unknown argument. |
| // & first argument has imaginary dash (ala tar/ps) |
| // If given twice, all arguments have imaginary dash |
| |
| // Notes from getopt man page |
| // - and -- cannot be arguments. |
| // -- force end of arguments |
| // - is a synonym for stdin in file arguments |
| // -abc means -a -b -c |
| |
| /* This uses a getopt-like option string, but not getopt() itself. We call |
| * it the get_opt string. |
| * |
| * Each option in the get_opt string corresponds to a bit position in the |
| * return value. The rightmost argument is (1<<0), the next to last is (1<<1) |
| * and so on. If the option isn't seen in argv[], its bit remains 0. |
| * |
| * Options which have an argument fill in the corresponding slot in the global |
| * union "this" (see generated/globals.h), which it treats as an array of longs |
| * (note that sizeof(long)==sizeof(pointer) is guaranteed by LP64). |
| * |
| * You don't have to free the option strings, which point into the environment |
| * space. List objects should be freed by main() when command_main() returns. |
| * |
| * Example: |
| * Calling get_optflags() when toys.which->options="ab:c:d" and |
| * argv = ["command", "-b", "fruit", "-d", "walrus"] results in: |
| * |
| * Changes to struct toys: |
| * toys.optflags = 5 (-b=4 | -d=1) |
| * toys.optargs[0]="walrus" (leftover argument) |
| * toys.optargs[1]=NULL (end of list) |
| * toys.optc=1 (there was 1 leftover argument) |
| * |
| * Changes to union this: |
| * this[0]=NULL (because -c didn't get an argument this time) |
| * this[1]="fruit" (argument to -b) |
| */ |
| |
| // Linked list of all known options (get_opt string is parsed into this). |
| struct opts { |
| struct opts *next; |
| long *arg; // Pointer into union "this" to store arguments at. |
| uint32_t edx[3]; // Flag mask to enable/disable/exclude. |
| int c; // Short argument character |
| int flags; // |=1, ^=2 |
| char type; // Type of arguments to store |
| }; |
| |
| // State during argument parsing. |
| struct getoptflagstate |
| { |
| int argc; |
| char *arg; |
| struct opts *opts, *this; |
| int noerror, nodash_now, stopearly; |
| uint32_t excludes; |
| }; |
| |
| // Parse one command line option. |
| |
| static int gotflag(struct getoptflagstate *gof) |
| { |
| int type; |
| struct opts *opt = gof->this; |
| |
| // Did we recognize this option? |
| if (!opt) { |
| if (gof->noerror) return 1; |
| error_exit("Unknown option %s", gof->arg); |
| } |
| toys.optflags |= opt->edx[0]; |
| toys.optflags &= ~opt->edx[1]; |
| gof->excludes = opt->edx[2]; |
| if (opt->flags&2) gof->stopearly=2; |
| |
| // Does this option take an argument? |
| gof->arg++; |
| type = opt->type; |
| if (type) { |
| |
| // Handle "-xblah" and "-x blah", but also a third case: "abxc blah" |
| // to make "tar xCjfv blah1 blah2 thingy" work like |
| // "tar -x -C blah1 -j -f blah2 -v thingy" |
| if (!gof->nodash_now && !gof->arg[0]) { |
| gof->arg = toys.argv[++gof->argc]; |
| // TODO: The following line doesn't display --longopt correctly |
| if (!gof->arg) error_exit("Missing argument to -%c",opt->c); |
| } |
| |
| // Grab argument. |
| if (!gof->arg && !(gof->arg = toys.argv[++(gof->argc)])) |
| error_exit("Missing argument"); |
| if (type == ':') *(opt->arg) = (long)gof->arg; |
| else if (type == '*') { |
| struct arg_list **list; |
| |
| list = (struct arg_list **)opt->arg; |
| while (*list) list=&((*list)->next); |
| *list = xzalloc(sizeof(struct arg_list)); |
| (*list)->arg = gof->arg; |
| } else if (type == '#') *(opt->arg) = atolx((char *)gof->arg); |
| else if (type == '@') ++*(opt->arg); |
| |
| gof->arg = ""; |
| } |
| |
| gof->this = NULL; |
| return 0; |
| } |
| |
| // Fill out toys.optflags and toys.optargs. |
| |
| static char *plustildenot = "+~!"; |
| void get_optflags(void) |
| { |
| int nodash = 0, minargs = 0, maxargs; |
| struct longopts { |
| struct longopts *next; |
| struct opts *opt; |
| char *str; |
| int len; |
| } *longopts = NULL; |
| struct getoptflagstate gof; |
| long *nextarg = (long *)&this, saveflags; |
| char *options = toys.which->options; |
| char *letters[]={"s",""}; |
| |
| if (CFG_HELP) toys.exithelp++; |
| // Allocate memory for optargs |
| maxargs = 0; |
| while (toys.argv[maxargs++]); |
| toys.optargs = xzalloc(sizeof(char *)*maxargs); |
| maxargs = INT_MAX; |
| bzero(&gof, sizeof(struct getoptflagstate)); |
| |
| // Parse option format |
| if (options) { |
| |
| // Parse leading special behavior indicators |
| for (;;) { |
| if (*options == '^') gof.stopearly++; |
| else if (*options == '<') minargs=*(++options)-'0'; |
| else if (*options == '>') maxargs=*(++options)-'0'; |
| else if (*options == '?') gof.noerror++; |
| else if (*options == '&') nodash++; |
| else break; |
| options++; |
| } |
| |
| if (!*options) gof.stopearly++; |
| // Parse rest of opts into array |
| while (*options) { |
| char *temp; |
| |
| // Allocate a new option entry when necessary |
| if (!gof.this) { |
| gof.this = xzalloc(sizeof(struct opts)); |
| gof.this->next = gof.opts; |
| gof.opts = gof.this; |
| ++*(gof.this->edx); |
| } |
| // Each option must start with "(" or an option character. (Bare |
| // longopts only come at the start of the string.) |
| if (*options == '(') { |
| char *end; |
| struct longopts *lo = xmalloc(sizeof(struct longopts)); |
| |
| // Find the end of the longopt |
| for (end = ++options; *end && *end != ')'; end++); |
| if (CFG_TOYBOX_DEBUG && !*end) |
| error_exit("Bug1 in get_opt"); |
| |
| // Allocate and init a new struct longopts |
| lo = xmalloc(sizeof(struct longopts)); |
| lo->next = longopts; |
| lo->opt = gof.this; |
| lo->str = options; |
| lo->len = end-options; |
| longopts = lo; |
| options = end; |
| |
| // Mark this as struct opt as used, even when no short opt. |
| if (!gof.this->c) gof.this->c = -1; |
| |
| // If this is the start of a new option that wasn't a longopt, |
| |
| } else if (strchr(":*#@", *options)) { |
| gof.this->type = *options; |
| } else if (0 != (temp = strchr(plustildenot, *options))) { |
| int i=0, idx = temp - plustildenot; |
| struct opts *opt; |
| |
| if (!*++options && CFG_TOYBOX_DEBUG) |
| error_exit("Bug2 in get_opt"); |
| // Find this option flag (in previously parsed struct opt) |
| for (opt = gof.this; ; opt = opt->next) { |
| if (CFG_TOYBOX_DEBUG && !opt) error_exit("Bug3 in get_opt"); |
| if (opt->c == *options) break; |
| i++; |
| } |
| gof.this->edx[idx] |= 1<<i; |
| |
| } else if (*options == '[') { |
| } else if (*options == '|') gof.this->flags |= 1; |
| else if (*options == '^') gof.this->flags |= 2; |
| |
| // At this point, we've hit the end of the previous option. The |
| // current character is the start of a new option. If we've already |
| // assigned an option to this struct, loop to allocate a new one. |
| // (It'll get back here afterwards and fall through to next else.) |
| else if(gof.this->c) { |
| gof.this = NULL; |
| continue; |
| |
| // Claim this option, loop to see what's after it. |
| } else gof.this->c = *options; |
| |
| options++; |
| } |
| } |
| |
| // Initialize enable/disable/exclude masks and pointers to store arguments. |
| // (We have to calculate all this ahead of time because longopts jump into |
| // the middle of the list.) |
| gof.argc = 0; |
| for (gof.this = gof.opts; gof.this; gof.this = gof.this->next) { |
| int i; |
| |
| for (i=0;i<3;i++) gof.this->edx[i] <<= gof.argc; |
| gof.argc++; |
| if (gof.this->type) { |
| gof.this->arg = (void *)nextarg; |
| *(nextarg++) = 0; |
| } |
| } |
| |
| // Iterate through command line arguments, skipping argv[0] |
| for (gof.argc=1; toys.argv[gof.argc]; gof.argc++) { |
| gof.arg = toys.argv[gof.argc]; |
| gof.this = NULL; |
| |
| // Parse this argument |
| if (gof.stopearly>1) goto notflag; |
| |
| gof.nodash_now = 0; |
| |
| // Various things with dashes |
| if (*gof.arg == '-') { |
| |
| // Handle - |
| if (!gof.arg[1]) goto notflag; |
| gof.arg++; |
| if (*gof.arg=='-') { |
| struct longopts *lo; |
| |
| gof.arg++; |
| // Handle -- |
| if (!*gof.arg) { |
| gof.stopearly += 2; |
| goto notflag; |
| } |
| // Handle --longopt |
| |
| for (lo = longopts; lo; lo = lo->next) { |
| if (!strncmp(gof.arg, lo->str, lo->len)) { |
| if (gof.arg[lo->len]) { |
| if (gof.arg[lo->len]=='=' && lo->opt->type) |
| gof.arg += lo->len; |
| else continue; |
| } |
| // It's a match. |
| gof.arg = ""; |
| gof.this = lo->opt; |
| break; |
| } |
| } |
| |
| // Should we handle this --longopt as a non-option argument? |
| if (!lo && gof.noerror) { |
| gof.arg-=2; |
| goto notflag; |
| } |
| |
| // Long option parsed, handle option. |
| gotflag(&gof); |
| continue; |
| } |
| |
| // Handle things that don't start with a dash. |
| } else { |
| if (nodash && (nodash>1 || gof.argc == 1)) gof.nodash_now = 1; |
| else goto notflag; |
| } |
| |
| // At this point, we have the args part of -args. Loop through |
| // each entry (could be -abc meaning -a -b -c) |
| saveflags = toys.optflags; |
| while (*gof.arg) { |
| |
| // Identify next option char. |
| for (gof.this = gof.opts; gof.this; gof.this = gof.this->next) |
| if (*gof.arg == gof.this->c) break; |
| |
| // Handle option char (advancing past what was used) |
| if (gotflag(&gof) ) { |
| toys.optflags = saveflags; |
| gof.arg = toys.argv[gof.argc]; |
| goto notflag; |
| } |
| } |
| continue; |
| |
| // Not a flag, save value in toys.optargs[] |
| notflag: |
| if (gof.stopearly) gof.stopearly++; |
| toys.optargs[toys.optc++] = toys.argv[gof.argc]; |
| } |
| |
| // Sanity check |
| if (toys.optc<minargs) { |
| error_exit("Need%s %d argument%s", letters[!!(minargs-1)], minargs, |
| letters[!(minargs-1)]); |
| } |
| if (toys.optc>maxargs) |
| error_exit("Max %d argument%s", maxargs, letters[!(maxargs-1)]); |
| if (CFG_HELP) toys.exithelp = 0; |
| } |