From 2c673900ceacf28684b332fc38e97f878f37d9ba Mon Sep 17 00:00:00 2001
From: Alexey Tourbin <at@altlinux.ru>
Date: Mon, 10 Jan 2011 13:02:49 +0300
Subject: [PATCH] build/interdep.c: initial revision

---
 build/Makefile.am |   6 +--
 build/files.c     |   4 ++
 build/interdep.c  | 124 ++++++++++++++++++++++++++++++++++++++++++++++
 build/interdep.h  |   7 +++
 4 files changed, 138 insertions(+), 3 deletions(-)
 create mode 100644 build/interdep.c
 create mode 100644 build/interdep.h

diff --git a/build/Makefile.am b/build/Makefile.am
index e765f38..2c5388e 100644
--- a/build/Makefile.am
+++ b/build/Makefile.am
@@ -12,12 +12,12 @@ LIBS =
 
 pkgincdir = $(pkgincludedir)
 pkginc_HEADERS = rpmbuild.h rpmspec.h
-noinst_HEADERS = buildio.h checkFiles.h
+noinst_HEADERS = buildio.h checkFiles.h interdep.h
 
 lib_LTLIBRARIES = librpmbuild.la
 librpmbuild_la_SOURCES = \
-	build.c checkFiles.c expression.c files.c misc.c names.c pack.c \
-	parseBuildInstallClean.c parseChangelog.c parseDescription.c \
+	build.c checkFiles.c expression.c files.c interdep.c misc.c names.c \
+	pack.c parseBuildInstallClean.c parseChangelog.c parseDescription.c \
 	parseFiles.c parsePreamble.c parsePrep.c parseReqs.c parseScript.c \
 	parseSpec.c poptBT.c reqprov.c spec.c
 librpmbuild_la_LDFLAGS = -release @VERSION@.1
diff --git a/build/files.c b/build/files.c
index 2d5ca92..dc15770 100644
--- a/build/files.c
+++ b/build/files.c
@@ -2909,6 +2909,7 @@ static void printDeps(Header h)
     versions = hfd(versions, dvt);
 }
 
+#include "interdep.h"
 #include "checkFiles.h"
 
 int processBinaryFiles(Spec spec, int installSpecialDoc, int test)
@@ -2939,6 +2940,9 @@ int processBinaryFiles(Spec spec, int installSpecialDoc, int test)
 	if (rc) break;
     }
 
+    if (rc == 0)
+	rc = processInterdep(spec);
+
     if (rc == 0)
 	rc = checkFiles(spec);
 
diff --git a/build/interdep.c b/build/interdep.c
new file mode 100644
index 0000000..05116fe
--- /dev/null
+++ b/build/interdep.c
@@ -0,0 +1,124 @@
+/*
+ * interdep.c - inter-package analysis and optimizations based on
+ * strict dependencies between subpackages (Requires: N = [E:]V-R).
+ *
+ * Written by Alexey Tourbin <at@altlinux.org>.
+ * License: GPLv2+.
+ */
+
+#include "system.h"
+#include "rpmbuild.h"
+#include "interdep.h"
+
+static
+const char *skipPrefixDash(const char *str, const char *prefix)
+{
+    int len = strlen(prefix);
+    if (strncmp(str, prefix, len))
+	return NULL;
+    if (str[len] != '-')
+	return NULL;
+    return str + len + 1;
+}
+
+struct Req {
+    int c;
+    struct Pair {
+	Package pkg1;
+	Package pkg2;
+    } *v;
+};
+
+static
+int Requires(struct Req *r, Package pkg1, Package pkg2)
+{
+    int i;
+    for (i = 0; i < r->c; i++)
+	if (pkg1 == r->v[i].pkg1 && pkg2 == r->v[i].pkg2)
+	    return 1;
+    return 0;
+}
+
+static
+void addRequires(struct Req *r, Package pkg1, Package pkg2)
+{
+    if (Requires(r, pkg1, pkg2))
+	return;
+    AUTO_REALLOC(r->v, r->c, 8);
+    r->v[r->c++] = (struct Pair) { pkg1, pkg2 };
+}
+
+static
+void makeReq1(struct Req *r, Package pkg1, Package pkg2)
+{
+    int c = 0;
+    const char **reqNv = NULL;
+    const char **reqVv = NULL;
+    const int *reqFv = NULL;
+    const HGE_t hge = (HGE_t)headerGetEntryMinMemory;
+    int ok =
+       hge(pkg1->header, RPMTAG_REQUIRENAME, NULL, (void **) &reqNv, &c) &&
+       hge(pkg1->header, RPMTAG_REQUIREVERSION, NULL, (void **) &reqVv, NULL) &&
+       hge(pkg1->header, RPMTAG_REQUIREFLAGS, NULL, (void **) &reqFv, NULL);
+    if (!ok)
+	return;
+    const char *provN, *provV, *provR;
+    headerNVR(pkg2->header, &provN, &provV, &provR);
+    int i;
+    for (i = 0; i < c; i++) {
+	if (strcmp(reqNv[i], provN))
+	    continue;
+	if ((reqFv[i] & RPMSENSE_SENSEMASK) != RPMSENSE_EQUAL)
+	    continue;
+	const char *reqVR = reqVv[i];
+	if (*reqVR == '\0')
+	    continue;
+	const char *reqR = skipPrefixDash(reqVR, provV);
+	if (reqR == NULL) {
+	    // XXX handle epoch properly?
+	    const char *colon = strchr(reqVR, ':');
+	    if (colon)
+		reqR = skipPrefixDash(colon + 1, provV);
+	}
+	if (reqR == NULL)
+	    continue;
+	if (strcmp(reqR, provR))
+	    continue;
+	addRequires(r, pkg1, pkg2);
+	break;
+    }
+    const HFD_t hfd = (HFD_t) headerFreeData;
+    reqNv = hfd(reqNv, RPM_STRING_ARRAY_TYPE);
+    reqVv = hfd(reqVv, RPM_STRING_ARRAY_TYPE);
+}
+
+static
+struct Req *makeRequires(Spec spec)
+{
+    struct Req *r = xmalloc(sizeof *r);
+    r->c = 0;
+    r->v = NULL;
+    Package pkg1, pkg2;
+    for (pkg1 = spec->packages; pkg1; pkg1 = pkg1->next)
+	for (pkg2 = pkg1->next; pkg2; pkg2 = pkg2->next) {
+	    makeReq1(r, pkg1, pkg2);
+	    makeReq1(r, pkg2, pkg1);
+	}
+    return r;
+}
+
+static
+struct Req *freeRequires(struct Req *r)
+{
+    r->v = _free(r->v);
+    return _free(r);
+}
+
+int processInterdep(Spec spec)
+{
+    struct Req *r = makeRequires(spec);
+    r = freeRequires(r);
+    return 0;
+}
+
+// ex: set ts=8 sts=4 sw=4 noet:
diff --git a/build/interdep.h b/build/interdep.h
new file mode 100644
index 0000000..ea052a9
--- /dev/null
+++ b/build/interdep.h
@@ -0,0 +1,7 @@
+#ifndef INTERDEP_H
+#define INTERDEP_H
+
+/* Perform inter-package analysis and optimizations. */
+int processInterdep(Spec spec);
+
+#endif