From e9afed34930887add2c54e08141bbf4d5a98c256 Mon Sep 17 00:00:00 2001
From: =?utf8?q?=E2=80=9Czg84=2Ezhang=E2=80=9D?= <zg84.zhang@samsung.com>
Date: Wed, 22 Feb 2023 11:11:16 +0800
Subject: [PATCH] Add setgenmetaalgo method to select the desired algorithm

https://src.fedoraproject.org/rpms/perl-BSSolv/blob/3dcce328e1068c089dcdaf105cd211033aef53dd/f/0001-Implement-genmetaalgo-1.patchhttps://src.fedoraproject.org/rpms/perl-BSSolv/blob/3dcce328e1068c089dcdaf105cd211033aef53dd/f/0001-Implement-genmetaalgo-1.patch
Change-Id: I0c2e3505993dced02485805221f0614a3ff85ddc
---
 BSSolv.xs | 65 ++++++++++++++++++++++++++++++++++++++++++++-------------------
 1 file changed, 46 insertions(+), 19 deletions(-)

diff --git a/BSSolv.xs b/BSSolv.xs
index e819aa9..68814e0 100644
--- a/BSSolv.xs
+++ b/BSSolv.xs
@@ -59,6 +59,7 @@ static Id buildservice_external;
 static Id buildservice_dodurl;
 static Id expander_directdepsend;
 static Id buildservice_dodcookie;
+static int genmetaalgo;
 
 /* make sure bit n is usable */
 #define MAPEXP(m, n) ((m)->size < (((n) + 8) >> 3) ? map_grow(m, n + 256) : 0)
@@ -1371,10 +1372,10 @@ create_considered(Pool *pool, Repo *repoonly, Map *considered)
 }
 
 struct metaline {
-  char *l;
-  int lastoff;
-  int nslash;
-  int killed;
+  char *l;           /* pointer to line */
+  int lastoff;       /* line offset of last path element */
+  int nslash;        /* number of slashes */
+  int killed;        /* 1: line has been killed. 2: because of a cycle package */
 };
 
 static int metacmp(const void *ap, const void *bp)
@@ -3719,6 +3720,18 @@ depsort(HV *deps, SV *mapp, SV *cycp, ...)
 	    solv_free(names);
 	}
 
+int
+setgenmetaalgo(int algo)
+    CODE:
+      if (algo < 0)
+          algo = 1;
+      if (algo > 1)
+          croak("BSSolv::setgenmetaalgo: unsupported algo %d\n", algo);
+      genmetaalgo = algo;
+      RETVAL = algo;
+    OUTPUT:
+      RETVAL
+
 void
 gen_meta(AV *subp, ...)
     PPCODE:
@@ -3804,7 +3817,7 @@ gen_meta(AV *subp, ...)
 		  }
 		if (cycle)
 		  {
-		    lp->killed = 1;
+		    lp->killed = 1; /* killed because line includes a subpackage */
 		    if (cycle > 1)	/* ignore self cycles */
 		      queue_push(&cycles, i);
 		  }
@@ -3820,9 +3833,9 @@ gen_meta(AV *subp, ...)
 		char *cycledata = 0;
 		int cycledatalen = 0;
 
+		/* create hash of cycle packages */
 		cycledata = solv_extend(cycledata, cycledatalen, 1, 1, 255);
-		cycledata[0] = 0;
-		cycledatalen += 1;
+		cycledata[cycledatalen++] = 0;
 		hm = mkmask(cycles.count);
 		ht = solv_calloc(hm + 1, sizeof(*ht));
 		for (i = 0; i < cycles.count; i++)
@@ -3840,18 +3853,22 @@ gen_meta(AV *subp, ...)
 			  break;
 		        h = HASHCHAIN_NEXT(h, hh, hm);
 		      }
-		    if (id)
-		      continue;
-		    cycledata = solv_extend(cycledata, cycledatalen, strlen(s) + 1, 1, 255);
-		    ht[h] = cycledatalen;
-		    strcpy(cycledata + cycledatalen, s);
-		    cycledatalen += strlen(s) + 1;
+		    if (!id)
+		      {
+		        int l = strlen(s);
+		        cycledata = solv_extend(cycledata, cycledatalen, l + 1, 1, 255);
+		        ht[h] = cycledatalen;	/* point to name */
+		        strcpy(cycledata + cycledatalen, s);
+		        cycledatalen += l + 1;
+		      }
 		    if (se)
 		      *se = '/';
 		  }
 		for (i = 0, lp = lines; i < nlines; i++, lp++)
 		  {
-		    if (lp->killed || !lp->nslash)
+		    if (!lp->nslash)
+		      continue;
+		    if (lp->killed && genmetaalgo == 0)
 		      continue;
 		    lo = strchr(lp->l + 34, '/') + 1;
 		    for (s2 = lo; *s2; s2++)
@@ -3869,12 +3886,12 @@ gen_meta(AV *subp, ...)
 			  *s2 = '/';
 			  if (id)
 			    {
-			      lp->killed = 1;
+			      lp->killed = 2;  /* killed because it containes a cycle package */
 			      break;
 			    }
 			  lo = s2 + 1;
 			}
-		    if (lp->killed)
+		    if (lp->killed == 2)
 		      continue;
 		    h = strhash(lo) & hm;
 		    hh = HASHCHAIN_START;
@@ -3886,13 +3903,13 @@ gen_meta(AV *subp, ...)
 		      }
 		    if (id)
 		      {
-		        lp->killed = 1;
+		        lp->killed = 2;	/* killed because it containes a cycle package */
 		      }
 		  }
 		solv_free(ht);
 		cycledata = solv_free(cycledata);
-		queue_free(&cycles);
 	      }
+	    queue_free(&cycles);
 
 	    /* cycles are pruned, now sort array */
 	    if (nlines > 1)
@@ -3903,7 +3920,10 @@ gen_meta(AV *subp, ...)
 	    for (i = 0, lp = lines; i < nlines; i++, lp++)
 	      {
 		if (lp->killed)
-		  continue;
+		  {
+	        if (genmetaalgo == 0 || lp->killed != 2)
+		      continue;
+		  }
 		s = lp->l;
 		h = strnhash(s, 10);
 		h = strhash_cont(s + lp->lastoff, h) & hm;
@@ -3915,6 +3935,13 @@ gen_meta(AV *subp, ...)
 		      break;
 		    h = HASHCHAIN_NEXT(h, hh, hm);
 		  }
+		if (id && genmetaalgo == 1 && lp->killed == 2)
+		  {
+		    /* also kill old line of same level */
+		    struct metaline *lp2 = lines + (id - 1);
+		    if (!lp2->killed && lp2->nslash == lp->nslash)
+		      lp2->killed = 1;
+		  }
 		if (id)
 		  lp->killed = 1;
 		else
-- 
2.7.4