3546 add support for grep -o option

@@ -32,10 +32,11 @@
 
 /* Copyright 2012 Nexenta Systems, Inc.  All rights reserved. */
 
 /*
  * Copyright 2013 Damian Bogel. All rights reserved.
+ * Copyright (c) 2013 Andrew Stormont.  All rights reserved.
  */
 
 /*
  * grep -- print lines matching (or not matching) a pattern
  *

@@ -100,10 +101,11 @@
 static int      iflag;
 static int      wflag;
 static int      hflag;
 static int      Hflag;
 static int      qflag;
+static int      oflag;
 static int      errflg;
 static int      nfile;
 static long long        tln;
 static int      nsucc;
 static int      outfn = 0;

@@ -128,11 +130,11 @@
 #if !defined(TEXT_DOMAIN)       /* Should be defined by cc -D */
 #define TEXT_DOMAIN "SYS_TEST"  /* Use this only if it weren't */
 #endif
         (void) textdomain(TEXT_DOMAIN);
 
-        while ((c = getopt(argc, argv, "hHqblcnRrsviyw")) != -1)
+        while ((c = getopt(argc, argv, "hHqblcnoRrsviyw")) != -1)
                 switch (c) {
                 /* based on options order h or H is set as in GNU grep */
                 case 'h':
                         hflag++;
                         Hflag = 0; /* h excludes H */

@@ -152,10 +154,13 @@
                         cflag++;
                         break;
                 case 'n':
                         nflag++;
                         break;
+                case 'o':
+                        oflag++;
+                        break;
                 case 'R':
                         Rflag++;
                         /* FALLTHROUGH */
                 case 'r':
                         rflag++;

@@ -180,11 +185,11 @@
                 case '?':
                         errflg++;
                 }
 
         if (errflg || (optind >= argc)) {
-                errmsg("Usage: grep [-c|-l|-q] [-r|-R] -hHbnsviw "
+                errmsg("Usage: grep [-c|-l|-q|-o] [-r|-R] -hHbnsviw "
                     "pattern file . . .\n",
                     (char *)NULL);
                 exit(2);
         }
 

@@ -411,12 +416,21 @@
                          * Use record as is
                          */
                         lbuf = ptr;
 
                 /* lflag only once */
-                if ((step(lbuf, expbuf) ^ vflag) && succeed(file) == 1)
+                if (step(lbuf, expbuf) ^ vflag) {
+                        if (oflag) {
+                                /*
+                                 * Only store the matching bits
+                                 */
+                                ptr = loc1;
+                                ptrend = loc2;
+                        }
+                        if (succeed(file) == 1)
                         break;
+                }
 
                 if (!nlflag)
                         break;
 
                 ptr = next_ptr;