commit - 92fd3a6469b82d5ed55b32049a9400852cd2cc0f
commit + acd47706189b842db4894473168a4dded897e245
blob - /dev/null
blob + a88e99f266537a722d3d3110ab9ba8b08a44516d (mode 644)
--- /dev/null
+++ src/cmd/getflags/funcgetflags.c
+#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(*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
