Supported operators: %elif, %elifarch, %elifos.

There may be several %elifs within the same %if statement.
They must be placed after %if and before %endif and %else
(if %else is contained). The first %elif expression (if any)
that evaluates to TRUE would be executed.

In scope of %if you can use any of the new operators - %elif, %elifarch,
%elifos. Similarly for %ifos, %ifnos, %ifarch and %ifnarch.

The expression after %elif (resp. %elifos or %elifarch) is expandedd iff
the expression can influence the execution of the %elif branch.
E.g.: an %elif expression after the first %elif expression that
evaluates to TRUE is not expanded.

build/parseSpec.c

@@ -230,9 +230,15 @@ static int expandMacrosInSpecBuf(rpmSpec spec, int strip)
 		condition->text, spec->lineNum, lbuf);
     }
 
+    /* Don't expand macros after %elif (resp. %elifarch, %elifos) in a false branch */
+    if (condition && (condition->id & LINE_ELIFANY)) {
+	if (!spec->readStack->readable)
+	    return 0;
     /* Don't expand macros (eg. %define) in false branch of %if clause */
-    if (!spec->readStack->reading)
-	return 0;
+    } else {
+	if (!spec->readStack->reading)
+	    return 0;
+    }
 
     if (specExpand(spec, ofi->lineNum, spec->lbuf, &lbuf))
 	return 1;
@@ -412,6 +418,7 @@ int readLine(rpmSpec spec, int strip)
     int startLine = 0;
     parsedSpecLine lineType;
     int prevType = spec->readStack->lastConditional->id;
+    int checkCondition;
 
     if (!restoreFirstChar(spec)) {
 retry:
@@ -463,19 +470,23 @@ int readLine(rpmSpec spec, int strip)
 	return PART_ERROR;
     }
 
-    if (lineType->id == LINE_IFARCH) {
+    if (lineType->id & (LINE_IFARCH | LINE_ELIFARCH)) {
 	ARGMATCH(s, "%{_target_cpu}", match);
     } else if (lineType->id == LINE_IFNARCH) {
 	ARGMATCH(s, "%{_target_cpu}", match);
 	match = !match;
-    } else if (lineType->id == LINE_IFOS) {
+    } else if (lineType->id & (LINE_IFOS | LINE_ELIFOS)) {
 	ARGMATCH(s, "%{_target_os}", match);
     } else if (lineType->id == LINE_IFNOS) {
 	ARGMATCH(s, "%{_target_os}", match);
 	match = !match;
-    } else if (lineType->id == LINE_IF) {
-	s += 3;
-	if (spec->readStack->reading) {
+    } else if (lineType->id & (LINE_IF | LINE_ELIF)) {
+	s += lineType->textLen;
+	if (lineType->id == LINE_IF)
+	    checkCondition = spec->readStack->reading;
+	else
+	    checkCondition = spec->readStack->readable;
+	if (checkCondition) {
 	    match = parseExpressionBoolean(s);
 	    if (match < 0) {
 		rpmlog(RPMLOG_ERR,
@@ -487,7 +498,7 @@ int readLine(rpmSpec spec, int strip)
     } else if (lineType->id == LINE_ELSE) {
 	spec->readStack->lastConditional = lineType;
 	spec->readStack->reading =
-	    spec->readStack->next->reading && ! spec->readStack->reading;
+	    spec->readStack->next->reading && spec->readStack->readable;
 	spec->line[0] = '\0';
     } else if (lineType->id == LINE_ENDIF) {
 	rl = spec->readStack;
@@ -517,14 +528,20 @@ int readLine(rpmSpec spec, int strip)
 	goto retry;
     }
 
-    if (lineType->id & (LINE_IFANY)) {
+    if (lineType->id & LINE_IFANY) {
 	rl = xmalloc(sizeof(*rl));
 	rl->reading = spec->readStack->reading && match;
 	rl->next = spec->readStack;
 	rl->lineNum = ofi->lineNum;
+	rl->readable = (!rl->reading) && (spec->readStack->reading);
 	rl->lastConditional = lineType;
 	spec->readStack = rl;
 	spec->line[0] = '\0';
+    } else if (lineType->id & LINE_ELIFANY) {
+	spec->readStack->reading = spec->readStack->readable && match;
+	if (spec->readStack->reading)
+	    spec->readStack->readable = 0;
+	spec->line[0] = '\0';
     }
 
 after_classification:

build/rpmbuild_internal.h

@@ -42,6 +42,9 @@ typedef enum rpmParseLineType_e {
     LINE_ELSE              = (1 << 5),
     LINE_ENDIF             = (1 << 6),
     LINE_INCLUDE           = (1 << 7),
+    LINE_ELIF              = (1 << 8),
+    LINE_ELIFARCH          = (1 << 9),
+    LINE_ELIFOS            = (1 << 10),
 } rpmParseLineType;
 
 typedef const struct parsedSpecLine_s {
@@ -62,14 +65,19 @@ static struct parsedSpecLine_s const lineTypes[] = {
     { LINE_IFOS,       LEN_AND_STR("%ifos")   , 1, 1, 0},
     { LINE_IFNOS,      LEN_AND_STR("%ifnos")  , 1, 1, 0},
     { LINE_INCLUDE,    LEN_AND_STR("%include"), 1, 0, 0},
+    { LINE_ELIFARCH,   LEN_AND_STR("%elifarch"), 1, 1, LINE_ENDIF | LINE_ELSE},
+    { LINE_ELIFOS,     LEN_AND_STR("%elifos"),  1, 1, LINE_ENDIF | LINE_ELSE},
+    { LINE_ELIF,       LEN_AND_STR("%elif")    ,1, 1, LINE_ENDIF | LINE_ELSE},
     { 0, 0, 0, 0, 0, 0 }
  };
 
 #define LINE_IFANY (LINE_IF | LINE_IFARCH | LINE_IFNARCH | LINE_IFOS | LINE_IFNOS)
+#define LINE_ELIFANY (LINE_ELIF | LINE_ELIFOS | LINE_ELIFARCH)
 
 typedef struct ReadLevelEntry {
     int reading;
     int lineNum;
+    int readable;
     parsedSpecLine lastConditional;
     struct ReadLevelEntry * next;
 } RLE_t;

build/spec.c

@@ -271,6 +271,7 @@ rpmSpec newSpec(void)
     spec->readStack->next = NULL;
     spec->readStack->reading = 1;
     spec->readStack->lastConditional = lineTypes;
+    spec->readStack->readable = 1;
 
     spec->rootDir = NULL;
     spec->prep = NULL;