Teach rpm about pre-transaction dependencies

- A pre-transaction dependency is generally anything that must be
  available at the start of the transaction, and cannot be resolved
  by packages *in* the transaction. This lets %pretrans scriptlet
  dependencies be expressed correctly, and could be also used for
  other kinds of pre-conditions.
- rpmlib() dependencies are a special case of pre-trans dependencies
  but leaving them handled separately as they cannot be provided by
  anything in rpmdb either, whereas pretrans dependencies can.

4 files changed, 15 insertions, 9 deletions

diff --git a/lib/depends.c b/lib/depends.c
index ec02a7b29..37bc0df63 100644
--- a/lib/depends.c
+++ b/lib/depends.c
@@ -364,6 +364,7 @@ static int unsatisfiedDepend(rpmts ts, depCache dcache, rpmds dep)
     int *cachedrc = NULL;
     int cacheThis = 0;
     int adding = (rpmdsInstance(dep) == 0);
+    rpmsenseFlags dsflags = rpmdsFlags(dep);
 
 retry:
     rc = 0;	/* assume dependency is satisfied */
@@ -373,7 +374,7 @@ retry:
      * on rpmlib provides. The dependencies look like "rpmlib(YaddaYadda)".
      * Check those dependencies now.
      */
-    if (rpmdsFlags(dep) & RPMSENSE_RPMLIB) {
+    if (dsflags & RPMSENSE_RPMLIB) {
 	static int oneshot = -1;
 	if (oneshot) 
 	    oneshot = rpmdsRpmlib(&rpmlibP, NULL);
@@ -385,8 +386,9 @@ retry:
 	goto unsatisfied;
     }
 
-    /* Search added packages for the dependency. */
-    if (rpmalSatisfiesDepend(tsmem->addedPackages, dep) != NULL) {
+    /* Pretrans dependencies can't be satisfied by added packages. */
+    if (!(dsflags & RPMSENSE_PRETRANS) &&
+		rpmalSatisfiesDepend(tsmem->addedPackages, dep) != NULL) {
 	goto exit;
     }
 
@@ -423,7 +425,8 @@ retry:
     /*
      * Search for an unsatisfied dependency.
      */
-    if (adding && !retrying && !(rpmtsFlags(ts) & RPMTRANS_FLAG_NOSUGGEST)) {
+    if (adding && !retrying && !(dsflags & RPMSENSE_PRETRANS) &&
+		!(rpmtsFlags(ts) & RPMTRANS_FLAG_NOSUGGEST)) {
 	xx = rpmtsSolve(ts, dep);
 	if (xx == 0)
 	    goto exit;
diff --git a/lib/formats.c b/lib/formats.c
index c13f46d92..07009553c 100644
--- a/lib/formats.c
+++ b/lib/formats.c
@@ -254,6 +254,8 @@ static char * deptypeFormat(rpmtd td, char * formatPrefix)
 	    argvAdd(&sdeps, "auto");
 	if (item & RPMSENSE_PREREQ)
 	    argvAdd(&sdeps, "prereq");
+	if (item & RPMSENSE_PRETRANS)
+	    argvAdd(&sdeps, "pretrans");
 
 	if (sdeps) {
 	    val = argvJoin(sdeps, ",");
diff --git a/lib/order.c b/lib/order.c
index f82ca6ac4..e0b69242c 100644
--- a/lib/order.c
+++ b/lib/order.c
@@ -165,8 +165,8 @@ static inline int addRelation(rpmts ts,
 
     dsflags = rpmdsFlags(requires);
 
-    /* Avoid rpmlib feature and package config dependencies */
-    if (dsflags & (RPMSENSE_RPMLIB|RPMSENSE_CONFIG))
+    /* Avoid dependendencies which are not relevant for ordering */
+    if (dsflags & (RPMSENSE_RPMLIB|RPMSENSE_CONFIG|RPMSENSE_PRETRANS))
 	return 0;
 
     q = rpmalSatisfiesDepend(al, requires);
diff --git a/lib/rpmds.h b/lib/rpmds.h
index 03ebf79fc..e71b86611 100644
--- a/lib/rpmds.h
+++ b/lib/rpmds.h
@@ -28,8 +28,8 @@ typedef	enum rpmsenseFlags_e {
     RPMSENSE_GREATER	= (1 << 2),
     RPMSENSE_EQUAL	= (1 << 3),
     /* bits 4-5 unused */
-    RPMSENSE_PREREQ	= (1 << 6), /* legacy prereq dependency */
-    /* bit 7 unused */
+    RPMSENSE_PREREQ	= (1 << 6), 	/* legacy prereq dependency */
+    RPMSENSE_PRETRANS	= (1 << 7),	/*!< Pre-transaction dependency. */
     RPMSENSE_INTERP	= (1 << 8),	/*!< Interpreter used by scriptlet. */
     RPMSENSE_SCRIPT_PRE	= (1 << 9),	/*!< %pre dependency. */
     RPMSENSE_SCRIPT_POST = (1 << 10),	/*!< %post dependency. */
@@ -67,11 +67,12 @@ typedef	enum rpmsenseFlags_e {
     RPMSENSE_FIND_REQUIRES | \
     RPMSENSE_RPMLIB | \
     RPMSENSE_KEYRING | \
+    RPMSENSE_PRETRANS | \
     RPMSENSE_PREREQ)
 
 #define	_notpre(_x)		((_x) & ~RPMSENSE_PREREQ)
 #define	_INSTALL_ONLY_MASK \
-    _notpre(RPMSENSE_SCRIPT_PRE|RPMSENSE_SCRIPT_POST|RPMSENSE_RPMLIB|RPMSENSE_KEYRING)
+    _notpre(RPMSENSE_SCRIPT_PRE|RPMSENSE_SCRIPT_POST|RPMSENSE_RPMLIB|RPMSENSE_KEYRING|RPMSENSE_PRETRANS)
 #define	_ERASE_ONLY_MASK  \
     _notpre(RPMSENSE_SCRIPT_PREUN|RPMSENSE_SCRIPT_POSTUN)