commit 3cd77ae67905c839ba2078e119f981d4f2284c7a
from: Russ Cox <rsc@swtch.com>
date: Wed Jul 15 06:48:37 2009 UTC

getflags: import from 4e, with usage

fixes #6 http://bitbucket.org/rsc/plan9port/issue/6/

http://codereview.appspot.com/95043

commit - 9bea9069bf3bc282c6b7d129926d4a0f1b40c66b
commit + 3cd77ae67905c839ba2078e119f981d4f2284c7a
blob - /dev/null
blob + bb0edf28d4f1d032702072a1c04f2e0d9b589f86 (mode 644)
--- /dev/null
+++ cmd/getflags.c
@@ -0,0 +1,82 @@
+#include <u.h>
+#include <libc.h>
+
+void
+usage(void)
+{
+	print("status=usage\n");
+	exits(0);
+}
+
+char*
+findarg(char *flags, Rune r)
+{
+	char *p;
+	Rune rr;
+	
+	for(p=flags; p!=(char*)1; p=strchr(p, ',')+1){
+		chartorune(&rr, p);
+		if(rr == r)
+			return p;
+	}
+	return nil;	
+}
+
+int
+countargs(char *p)
+{
+	int n;
+
+	n = 1;
+	while(*p == ' ')
+		p++;
+	for(; *p && *p != ','; p++)
+		if(*p == ' ' && *(p-1) != ' ')
+			n++;
+	return n;
+}
+
+void
+main(int argc, char *argv[])
+{
+	char *flags, *p, buf[512];
+	int i, n;
+	Fmt fmt;
+	
+	quotefmtinstall();
+	argv0 = argv[0];	/* for sysfatal */
+	
+	flags = getenv("flagfmt");
+	if(flags == nil){
+		fprint(2, "$flagfmt not set\n");
+		print("exit 'missing flagfmt'");
+		exits(0);
+	}
+
+	fmtfdinit(&fmt, 1, buf, sizeof buf);
+	for(p=flags; p!=(char*)1; p=strchr(p, ',')+1)
+		fmtprint(&fmt, "flag%.1s=()\n", p);
+	ARGBEGIN{
+	default:
+		if((p = findarg(flags, ARGC())) == nil)
+			usage();
+		p += runelen(ARGC());
+		if(*p == ',' || *p == 0){
+			fmtprint(&fmt, "flag%C=1\n", ARGC());
+			break;
+		}
+		n = countargs(p);
+		fmtprint(&fmt, "flag%C=(", ARGC());
+		for(i=0; i<n; i++)
+			fmtprint(&fmt, "%s%q", i ? " " : "", EARGF(usage()));
+		fmtprint(&fmt, ")\n");
+	}ARGEND
+	
+	fmtprint(&fmt, "*=(");
+	for(i=0; i<argc; i++)
+		fmtprint(&fmt, "%s%q", i ? " " : "", argv[i]);
+	fmtprint(&fmt, ")\n");
+	fmtprint(&fmt, "status=''\n");
+	fmtfdflush(&fmt);
+	exits(0);
+}
blob - /dev/null
blob + b064feaf1e632fd6c7233f98064bea8f294a1038 (mode 644)
--- /dev/null
+++ cmd/usage.c
@@ -0,0 +1,72 @@
+#include <u.h>
+#include <libc.h>
+
+void
+main(int argc, char **argv)
+{
+	Fmt fmt;
+	char buf[512];
+	char *argv0, *args, *flags, *p, *p0;
+	int single;
+	Rune r;
+	
+	argv0 = getenv("0");
+	if(argv0 == nil) {
+		if(argc > 1)
+			argv0 = argv[1];
+		else
+			argv0 = "unknown-program-name";
+	}
+	if((p = strrchr(argv0, '/')) != nil)
+		argv0 = p+1;
+	flags = getenv("flagfmt");
+	args = getenv("args");
+	
+	if(argv0 == nil){
+		fprint(2, "aux/usage: $0 not set\n");
+		exits("$0");
+	}
+	if(flags == nil)
+		flags = "";
+	if(args == nil)
+		args = "";
+
+	fmtfdinit(&fmt, 2, buf, sizeof buf);
+	fmtprint(&fmt, "usage: %s", argv0);
+	if(flags[0]){
+		single = 0;
+		for(p=flags; *p; ){
+			p += chartorune(&r, p);
+			if(*p == ',' || *p == 0){
+				if(!single){
+					fmtprint(&fmt, " [-");
+					single = 1;
+				}
+				fmtprint(&fmt, "%C", r);
+				if(*p == ',')
+					p++;
+				continue;
+			}
+			while(*p == ' ')
+				p++;
+			if(single){
+				fmtprint(&fmt, "]");
+				single = 0;
+			}
+			p0 = p;
+			p = strchr(p0, ',');
+			if(p == nil)
+				p = "";
+			else
+				*p++ = 0;
+			fmtprint(&fmt, " [-%C %s]", r, p0);
+		}
+		if(single)
+			fmtprint(&fmt, "]");
+	}
+	if(args)
+		fmtprint(&fmt, " %s", args);
+	fmtprint(&fmt, "\n");
+	fmtfdflush(&fmt);
+	exits("usage");
+}
blob - /dev/null
blob + 50274d4079a9fb4224a0f7dc5c690e28401930ed (mode 644)
--- /dev/null
+++ man8/getflags.8
@@ -0,0 +1,77 @@
+.TH GETFLAGS 8
+.SH NAME
+getflags, usage \- command-line parsing for shell scripts
+.SH SYNOPSIS
+.B getflags $*
+.PP
+.B usage [ progname ]
+.SH DESCRIPTION
+.I Getflags
+parses the options in its command-line arguments
+according to the environment variable
+.BR $flagfmt .
+This variable should be a list of comma-separated options.
+Each option can be a single letter, indicating that it does
+not take arguments, or a letter followed by the space-separated
+names of its arguments.
+.I Getflags 
+prints an 
+.IR rc (1)
+script on standard output which initializes the
+environment variable
+.BI $flag x
+for every option mentioned in 
+.BR $flagfmt .
+If the option is not present on the command-line, the script
+sets that option's flag variable to an empty list.
+Otherwise, the script sets that option's flag variable with
+a list containing the option's arguments or, 
+if the option takes no arguments,
+with the string
+.BR 1 .
+The script also sets the variable
+.B $*
+to the list of arguments following the options.
+The final line in the script sets the
+.B $status
+variable, to the empty string on success
+and to the string
+.B usage
+when there is an error parsing the command line.
+.PP
+.I Usage
+prints a usage message to standard error.
+It creates the message using
+.BR $flagfmt ,
+as described above,
+.BR $args ,
+which should contain the string to be printed explaining
+non-option arguments,
+and
+.BR $0 ,
+the program name
+(see
+.IR rc (1)).
+If run under 
+.IR sh (1),
+which does not set
+.BR $0 ,
+the program name must be given explicitly on the command line.
+.SH EXAMPLE
+Parse the arguments for
+.IR leak (1):
+.IP
+.EX
+flagfmt='b,s,f binary,r res,x width'
+args='name | pid list'
+if(! ifs=() eval `{getflags $*} || ~ $#* 0){
+	usage
+	exit usage
+}
+.EE
+.SH SOURCE
+.B \*9/src/cmd/getflags.c
+.br
+.B \*9/src/cmd/usage.c
+.SH SEE ALSO
+.IR arg (3)
blob - d0686679ab30456b2dada45c6f1d1032b0ee8bf2
blob + e69de29bb2d1d6434b8b29ae775ad8c2e48c5391
--- src/cmd/getflags/funcgetflags.c
+++ src/cmd/getflags/funcgetflags.c
@@ -1,267 +0,0 @@
-#include <u.h>
-#include <libc.h>
-#include <ctype.h>
-#include "getflags.h"
-
-char **flag[NFLAG];
-char cmdline[NCMDLINE+1];
-char *cmdname;
-char *flagset[];
-char *flagset[]={"<flag>"};
-static char *flagarg="";
-static void reverse(char **, char **);
-static int scanflag(int, char *);
-static int reason;
-#define	RESET	1
-#define	ARGCCOUNT	2
-#define	FLAGSYN	3
-#define	BADFLAG	4
-static int badflag;
-char *getflagsargv[NGETFLAGSARGV+2];	/* original argv stored here for people who need it */
-
-int
-getflags(int argc, char *argv[], char *flags)
-{
-	char *s, *t;
-	int i, j, c, count;
-	flagarg=flags;
-	if(cmdname==0){
-		cmdname=argv[0];
-		for(i=0;i!=argc && i!=NGETFLAGSARGV;i++) getflagsargv[i]=argv[i];
-		if(argc>NGETFLAGSARGV) getflagsargv[i++]="...";
-		getflagsargv[i]=0;
-	}
-	s=cmdline;
-	for(i=0;i!=argc;i++){
-		for(t=argv[i];*t;)
-			if(s!=&cmdline[NCMDLINE])
-				*s++=*t++;
-			else
-				break;
-		if(i!=argc-1 && s!=&cmdline[NCMDLINE])
-			*s++=' ';
-	}
-	*s='\0';
-	i=1;
-	while(i!=argc && argv[i][0]=='-'){
-		s=argv[i]+1;
-		if(*s=='\0'){	/* if argument is "-", stop scanning and delete it */
-			for(j=i+1;j<=argc;j++)
-				argv[j-1]=argv[j];
-			return argc-1;
-		}
-		while(*s){
-			c=*s++;
-			count=scanflag(c, flags);
-			if(count==-1) return -1;
-			if(flag[c]){ reason=RESET; badflag=c; return -1; }
-			if(count==0){
-				flag[c]=flagset;
-				if(*s=='\0'){
-					for(j=i+1;j<=argc;j++)
-						argv[j-1]=argv[j];
-					--argc;
-				}
-			}
-			else{
-				if(*s=='\0'){
-					for(j=i+1;j<=argc;j++)
-						argv[j-1]=argv[j];
-					--argc;
-					s=argv[i];
-				}
-				if(argc-i<count){
-					reason=ARGCCOUNT;
-					badflag=c;
-					return -1;
-				}
-				reverse(argv+i, argv+argc);
-				reverse(argv+i, argv+argc-count);
-				reverse(argv+argc-count+1, argv+argc);
-				argc-=count;
-				flag[c]=argv+argc+1;
-				flag[c][0]=s;
-				s="";
-			}
-		}
-	}
-	return argc;
-}
-
-void
-static reverse(char **p, char **q)
-{
-	register char *t;
-	for(;p<q;p++,--q){ t=*p; *p=*q; *q=t; }
-}
-
-static int
-scanflag(int c, char *f)
-{
-	int fc, count;
-	if(0<=c && c<NFLAG) while(*f){
-		if(*f==' '){
-			f++;
-			continue;
-		}
-		fc=*f++;
-		if(*f==':'){
-			f++;
-			if(!isdigit((uchar)*f)){ reason=FLAGSYN; return -1; }
-			count=strtol(f, &f, 10);
-		}
-		else
-			count=0;
-		if(*f=='['){
-			int depth=1;
-			do{
-				f++;
-				if(*f=='\0'){ reason=FLAGSYN; return -1; }
-				if(*f=='[') depth++;
-				if(*f==']') depth--;
-			}while(depth>0);
-			f++;
-		}
-		if(c==fc) return count;
-	}
-	reason=BADFLAG;
-	badflag=c;
-	return -1;
-}
-
-static void errn(char *, int), errs(char *), errc(int);
-
-void
-usage(char *tail)
-{
-	char *s, *t, c;
-	int count, nflag=0;
-	switch(reason){
-	case RESET:
-		errs("Flag -");
-		errc(badflag);
-		errs(": set twice\n");
-		break;
-	case ARGCCOUNT:
-		errs("Flag -");
-		errc(badflag);
-		errs(": too few arguments\n");
-		break;
-	case FLAGSYN:
-		errs("Bad argument to getflags!\n");
-		break;
-	case BADFLAG:
-		errs("Illegal flag -");
-		errc(badflag);
-		errc('\n');
-		break;
-	}
-	errs("Usage: ");
-	errs(cmdname);
-	for(s=flagarg;*s;){
-		c=*s;
-		if(*s++==' ') continue;
-		if(*s==':'){
-			s++;
-			count=strtol(s, &s, 10);
-		}
-		else count=0;
-		if(count==0){
-			if(nflag==0) errs(" [-");
-			nflag++;
-			errc(c);
-		}
-		if(*s=='['){
-			int depth=1;
-			s++;
-			for(;*s!='\0' && depth>0; s++)
-				if (*s==']') depth--;
-				else if (*s=='[') depth++;
-		}
-	}
-	if(nflag) errs("]");
-	for(s=flagarg;*s;){
-		c=*s;
-		if(*s++==' ') continue;
-		if(*s==':'){
-			s++;
-			count=strtol(s, &s, 10);
-		}
-		else count=0;
-		if(count!=0){
-			errs(" [-");
-			errc(c);
-			if(*s=='['){
-				int depth=1;
-				s++;
-				t=s;
-				for(;*s!='\0' && depth>0; s++)
-					if (*s==']') depth--;
-					else if (*s=='[') depth++;
-				errs(" ");
-				errn(t, s-t);
-			}
-			else
-				while(count--) errs(" arg");
-			errs("]");
-		}
-		else if(*s=='['){
-			int depth=1;
-			s++;
-			for(;*s!='\0' && depth>0; s++)
-				if (*s==']') depth--;
-				else if (*s=='[') depth++;
-		}
-	}
-	if(tail){
-		errs(" ");
-		errs(tail);
-	}
-	errs("\n");
-	exits("usage");
-}
-
-static void
-errn(char *s, int count)
-{
-	while(count){ errc(*s++); --count; }
-}
-
-static void
-errs(char *s)
-{
-	while(*s) errc(*s++);
-}
-
-#define	NBUF	80
-static char buf[NBUF], *bufp=buf;
-
-static void
-errc(int c){
-	*bufp++=c;
-	if(bufp==&buf[NBUF] || c=='\n'){
-		write(2, buf, bufp-buf);
-		bufp=buf;
-	}
-}
-
-#ifdef TEST
-#include <stdio.h>
-main(int argc, char *argv[])
-{
-	int c, i, n;
-	if(argc<3){
-		fprint(2, "Usage: %s flags cmd ...\n", argv[0]);
-		exits("usage");
-	}
-	n=getflags(argc-2, argv+2, argv[1]);
-	if(n<0) usage("...");
-	putchar('\n');
-	for(c=0;c!=128;c++) if(flag[c]){
-		print("\t-.%c. ", c);
-		n=scanflag(c, argv[1]);
-		for(i=0;i!=n;i++) print(" <%s>", flag[c][i]);
-		putchar('\n');
-	}
-}
-#endif
blob - 781da33c685b810f1f85e95478b7807708c19ac5
blob + e69de29bb2d1d6434b8b29ae775ad8c2e48c5391
--- src/cmd/getflags/getflags.c
+++ src/cmd/getflags/getflags.c
@@ -1,199 +0,0 @@
-/*% cyntax % && cc -go # %
- * getflags: process flags for command files
- * Usage: ifs='' eval `{getflags [-s] flagfmt [arg ...]}	# rc
- * Usage: IFS=   eval `getflags -b [-s] flagfmt [arg...]`	# Bourne shell
- *	-b means give Bourne-shell compatible output
- */
-#include <u.h>
-#include <libc.h>
-#include "getflags.h"
-
-/* predefine functions */
-void bourneprint(int, char *[]);
-void bournearg(char *);
-void rcprint(int, char *[]);
-void usmsg(char *);
-int count(int, char *);
-void rcarg(char *);
-
-void
-main(int argc, char *argv[])
-{
-	int bourne;
-	argc=getflags(argc, argv, "b");
-	if(argc<2) usage("flagfmt [arg ...]");
-	bourne=flag['b']!=0;
-	flag['b']=0;
-	if((argc=getflags(argc-1, argv+1, argv[1]))<0){
-		usmsg(argv[1]);
-		exits(0);
-	}
-	if(bourne) bourneprint(argc, argv);
-	else rcprint(argc, argv);
-	exits(0);
-}
-void
-bourneprint(int argc, char *argv[])
-{
-	register int c, i, n;
-	for(c=0;c!=NFLAG;c++) if(flag[c]){
-		print("FLAG%c=", c);		/* bug -- c could be a bad char */
-		n=count(c, argv[1]);
-		if(n==0)
-			print("1\n");
-		else{
-			print("'");
-			bournearg(flag[c][0]);
-			for(i=1;i!=n;i++){
-				print(" ");
-				bournearg(flag[c][i]);
-			}
-			print("'\n");
-		}
-	}
-	print("set --");
-	for(c=1;c!=argc;c++){
-		print(" ");
-		bournearg(argv[c+1]);
-	}
-	print("\n");
-}
-void
-bournearg(char *s)
-{
-	for(;*s;s++)
-		if(*s=='\'')
-			print("'\\''");
-		else
-			print("%c", *s);
-}
-void
-rcprint(int argc, char *argv[])
-{
-	int c, i, n;
-	for(c=0;c!=NFLAG;c++) if(flag[c]){
-		print("FLAG%c=", c);		/* bug -- c could be a bad char */
-		n=count(c, argv[1]);
-		if(n==0)
-			print("''");
-		else if(n==1)
-			rcarg(flag[c][0]);
-		else{
-			print("(");
-			rcarg(flag[c][0]);
-			for(i=1;i!=n;i++){
-				print(" ");
-				rcarg(flag[c][i]);
-			}
-			print(")");
-		}
-		print("\n");
-	}
-	print("*=");
-	if(argc==1) print("()");
-	else if(argc==2) rcarg(argv[2]);
-	else{
-		print("(");
-		rcarg(argv[2]);
-		for(c=2;c!=argc;c++){
-			print(" ");
-			rcarg(argv[c+1]);
-		}
-		print(")");
-	}
-	print("\n");
-}
-void
-usmsg(char *flagarg)
-{
-	char *s, *t, c;
-	int count, nflag=0;
-	print("echo Usage: $0'");
-	for(s=flagarg;*s;){
-		c=*s;
-		if(*s++==' ') continue;
-		if(*s==':')
-			count = strtol(s+1, &s, 10);
-		else count=0;
-		if(count==0){
-			if(nflag==0) print(" [-");
-			nflag++;
-			print("%c", c);
-		}
-		if(*s=='['){
-			int depth=1;
-			s++;
-			for(;*s!='\0' && depth>0; s++)
-				if (*s==']') depth--;
-				else if (*s=='[') depth++;
-		}
-	}
-	if(nflag) print("]");
-	for(s=flagarg;*s;){
-		c=*s;
-		if(*s++==' ') continue;
-		if(*s==':')
-			count = strtol(s+1, &s, 10);
-		else count=0;
-		if(count!=0){
-			print(" [-");
-			print("%c", c);
-			if(*s=='['){
-				int depth=1;
-				s++;
-				t=s;
-				for(;*s!='\0' && depth>0; s++)
-					if (*s==']') depth--;
-					else if (*s=='[') depth++;
-				print(" ");
-				write(1, t, s - t);
-			}
-			else
-				while(count--) print(" arg");
-			print("]");
-		}
-		else if(*s=='['){
-			int depth=1;
-			s++;
-			for(;*s!='\0' && depth>0; s++)
-				if (*s==']') depth--;
-				else if (*s=='[') depth++;
-		}
-	}
-	print("' $usage;\n");
-	print("exit 'usage'\n");
-}
-int
-count(int flag, char *flagarg)
-{
-	char *s, c;
-	int n;
-	for(s=flagarg;*s;){
-		c=*s;
-		if(*s++==' ') continue;
-		if(*s==':')
-			n = strtol(s+1, &s, 10);
-		else n=0;
-		if(*s=='['){
-			int depth=1;
-			s++;
-			for(;*s!='\0' && depth>0; s++)
-				if (*s==']') depth--;
-				else if (*s=='[') depth++;
-		}
-		if(c==flag) return n;
-	}
-	return -1;		/* never happens */
-}
-void
-rcarg(char *s)
-{
-	if(*s=='\0' || strpbrk(s, "\n \t#;&|^$=`'{}()<>?")){
-		print("\'");
-		for(;*s;s++)
-			if(*s=='\'') print("''");
-			else print("%c", *s);
-		print("\'");
-	}
-	else	print("%s", s);
-}
blob - ca7167b258ff96f2230daedb53d0146b81c6c737
blob + e69de29bb2d1d6434b8b29ae775ad8c2e48c5391
--- src/cmd/getflags/getflags.h
+++ src/cmd/getflags/getflags.h
@@ -1,10 +0,0 @@
-#define	NFLAG	128
-#define	NCMDLINE	512
-#define	NGETFLAGSARGV	256
-extern char **flag[NFLAG];
-extern char cmdline[NCMDLINE+1];
-extern char *cmdname;
-extern char *flagset[];
-extern char *getflagsargv[NGETFLAGSARGV+2];
-int getflags(int, char *[], char *);
-void usage(char *);
blob - fab59aa5e3293aa56e988e7f3e3e3b867a40f91b
blob + e69de29bb2d1d6434b8b29ae775ad8c2e48c5391
--- src/cmd/getflags/mkfile
+++ src/cmd/getflags/mkfile
@@ -1,9 +0,0 @@
-<$PLAN9/src/mkhdr
-
-TARG=getflags
-OFILES=\
-	getflags.$O\
-	funcgetflags.$O\
-
-<$PLAN9/src/mkone
-