From: Ralph Ronnquist <ralph.ronnquist@gmail.com>
Date: Thu, 11 Nov 2021 08:08:18 +0000 (+1100)
Subject: new function stralloc
X-Git-Url: https://git.rrq.au/?a=commitdiff_plain;h=37f43d2aa3f135a7fff1ca03552a4468b07f3390;p=rrq%2Ffuse_xattrs.git

new function stralloc
---

diff --git a/stringmem.c b/stringmem.c
index 303add7..1a6bf00 100644
--- a/stringmem.c
+++ b/stringmem.c
@@ -11,13 +11,27 @@ static struct {
     char *end;
 } heap;
 
-char *strjoin(const char *first,...) {
-    va_list ap;
+static inline void strinitialize() {
     if ( heap.base == 0 ) {
 	heap.base = (char*) malloc( STRINGSPACE );
 	heap.current = heap.base;
 	heap.end = heap.base + STRINGSPACE;
     }
+}
+
+extern char *stralloc(int size) {
+    strinitialize();
+    if ( heap.current + size >= heap.end ) {
+	heap.current = heap.base;
+    }
+    char *start = heap.current;
+    heap.current += size;
+    return start;
+}
+
+char *strjoin(const char *first,...) {
+    va_list ap;
+    strinitialize();
     char *start = heap.current;
     const char *p = first;
     size_t size = strlen( first ) + 1;
@@ -29,7 +43,7 @@ char *strjoin(const char *first,...) {
     if ( size > BIGSTRING ) {
 	start = (char*) malloc( size );
     } else {
-	if ( heap.current + size > heap.end ) {
+	if ( heap.current + size >= heap.end ) {
 	    heap.current = heap.base;
 	}
 	start = heap.current;
diff --git a/stringmem.h b/stringmem.h
index c25218f..1a3f695 100644
--- a/stringmem.h
+++ b/stringmem.h
@@ -1,6 +1,9 @@
 
-// Concatenate strigns onto the heap if possible, or malloc new.
+// Concatenate strings onto the heap if possible, or malloc new.
 extern char *strjoin(const char *first,...);
 
+// Allocate buffer space from the heap
+extern char *stralloc(int size);
+
 // Dispose memory possibly within the string heap
 extern void strfree(char *p);