New option parsing infrastructure (doesn't use getopt). Hook it up to

existing applets.  Still a bit buggy, but bits of it work.

1 files changed, 284 insertions, 0 deletions

diff --git a/lib/args.c b/lib/args.c
new file mode 100644
index 00000000..09b04d83
--- /dev/null
+++ b/lib/args.c
@@ -0,0 +1,284 @@
+/* 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)
+//     | this is required.  If more than one marked, only one required.
+//     (longopt)
+//     +X enabling this enables X (switch on)
+//     ~X enabling this disables X (switch off)
+//       x~x means toggle x, I.E. specifying it again switches it 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
+//     ? return array of remaining arguments in first vararg
+//     <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.
+ * 
+ *   Each option in options corresponds to a bit position in the return
+ * value (last argument is (1<<0), the next to last is (1<<1) and so on.
+ * If the option isn't seen in argv its bit is 0.  Options which have an
+ * argument use the next vararg.  (So varargs used by options go from left to
+ * right, but bits set by arguments go from right to left.)
+ *
+ * Example:
+ *   get_optflags("ab:c:d", NULL, &bstring, &cstring);
+ *   argv = ["command", "-b", "fruit", "-d"]
+ *   flags = 5, bstring="fruit", cstring=NULL;
+ */
+
+struct opts {
+	struct opts *next;
+	char c;
+	int type;
+	int shift;
+	void *arg;
+};
+
+struct getoptflagstate
+{
+	int argc;
+	char *arg;
+	struct opts *opts, *this;
+	int noerror, nodash_now;
+};
+
+static struct getoptflagstate gof;
+
+// Returns zero if it didn't consume the rest of the current -abcdef
+static int gotflag(void)
+{
+	char *arg = NULL;
+	int type;
+	int ret = 0;
+
+	// Did we recognize this option?
+	if (!gof.this && !gof.noerror) error_exit("Unknown option %s\n", gof.arg);
+	else toys.optflags |= 1 << gof.this->shift;
+
+	// Does this option take an argument?
+	gof.arg++;
+	if (gof.this->type & 255) {
+		// Make "tar xCjfv blah1 blah2 thingy" work like
+		// "tar -x -C blah1 -j -f blah2 -v thingy"
+		if (!gof.nodash_now && !*gof.arg) {
+			gof.arg = toys.argv[++gof.argc];
+			if (!gof.arg) error_exit("Missing argument");
+		} else {
+			arg = gof.arg;
+			ret++;
+		}
+	} else gof.this = NULL;
+
+	// If the last option had an argument, grab it.
+	if (!gof.this)  return 0;
+	type = gof.this->type & 255;
+	if (!gof.arg && !(gof.arg = toys.argv[++gof.argc]))
+		error_exit("Missing argument");
+	if (type == ':') gof.this->arg = arg;
+	else if (type == '*') {
+		struct arg_list *temp, **list;
+		list = (struct arg_list **)gof.this->arg;
+		temp = xmalloc(sizeof(struct arg_list));
+		temp->arg = arg;
+		temp->next = *list;
+		*list = temp;
+	} else if (type == '?') {
+	} else if (type == '@') {
+	}
+
+	return ret;
+}
+
+// Fill out toys.optflags and toys.optargs.  This isn't reentrant because
+// we don't bzero(&gof, sizeof(gof));
+
+void get_optflags(void)
+{
+	int stopearly = 0, optarg = 0, nodash = 0, minargs = 0, maxargs = INT_MAX;
+	struct longopts {
+		struct longopts *next;
+		struct opts *opt;
+		char *str;
+		int len;
+	} *longopts = NULL;
+	long *nextarg = (long *)&toy;
+	char *options = toys.which->options;
+
+	// Parse leading special behavior indicators
+	for (;;) {
+		if (*options == '+') 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++;
+	}
+
+	// Parse rest of opts into array
+	while (*options) {
+
+		// 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;
+		}
+		// 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_DEBUG && !*end) error_exit("Unterminated optstring");
+
+			// 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;
+
+			// For leading longopts (with no corresponding short opt), note
+			// that this option struct has been used.
+			gof.this->shift++;
+
+		// If this is the start of a new option that wasn't a longopt,
+
+		} else if (index(":*?@", *options)) {
+			gof.this->type |= *options;
+			// Pointer and long guaranteed to be the same size by LP64.
+			*(++nextarg) = 0;
+			gof.this->arg = (void *)nextarg;
+		} else if (*options == '|') {
+		} else if (*options == '+') {
+		} else if (*options == '~') {
+		} else if (*options == '!') {
+		} else if (*options == '[') {
+
+		// 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.)
+		} else if(gof.this->shift || gof.this->c) {
+			gof.this = NULL;
+			continue;
+
+		// Claim this option, loop to see what's after it.
+		} else gof.this->c = *options;
+
+		options++;
+	}
+
+	// Initialize shift bits (have to calculate this ahead of time because
+	// longopts jump into the middle of the list), and allocate space to
+	// store optargs.
+	gof.argc = 0;
+	for (gof.this = gof.opts; gof.this; gof.this = gof.this->next)
+		gof.this->shift = gof.argc++;
+	toys.optargs = xzalloc(sizeof(char *)*(++gof.argc));
+
+	// Iterate through command line arguments, skipping argv[0]
+	for (gof.argc=1; toys.argv[gof.argc]; gof.argc++) {
+		char *arg = toys.argv[gof.argc];
+
+		// Parse this argument
+		if (stopearly>1) goto notflag;
+
+		gof.nodash_now = 0;
+
+		// Various things with dashes
+		if (*arg == '-') {
+
+			// Handle -
+			if (!arg[1]) goto notflag;
+			arg++;
+			if (*arg=='-') {
+				struct longopts *lo;
+
+				arg++;
+				// Handle --
+				if (!*arg) {
+					stopearly += 2;
+					goto notflag;
+				}
+				// Handle --longopt
+
+				for (lo = longopts; lo; lo = lo->next) {
+					if (!strncmp(arg, lo->str, lo->len)) {
+						if (arg[lo->len]) {
+							if (arg[lo->len]=='='
+								&& (lo->opt->type & 255))
+							{
+								arg += lo->len;
+							} else continue;
+
+						// *options should be nul, this makes sure
+						// that the while (*arg) loop terminates;
+						} arg = options-1;
+						gof.this = lo->opt;
+						break;
+					}
+				}
+				// Long option parsed, jump to option handling.
+				gotflag();
+				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)
+		while (*arg) {
+			// Identify next option char.
+			for (gof.this = gof.opts; gof.this && *arg != gof.this->c;
+					gof.this = gof.this->next);
+			if (gotflag()) break;
+			arg++;
+		}
+		continue;
+
+		// Not a flag, save value in toys.optargs[]
+notflag:
+		if (stopearly) stopearly++;
+		toys.optargs[optarg++] = toys.argv[gof.argc];
+	}
+
+	// Sanity check
+	if (optarg<minargs) error_exit("Need %d arguments", minargs);
+	if (optarg>maxargs) error_exit("Max %d arguments", maxargs);
+}