From: Matthew Fernandez <matthew.fernandez@gmail.com>
Date: Sat, 24 Jul 2021 02:26:37 +0000 (-0700)
Subject: eval: avoid sfprintf in integer-to-string dynamic
X-Git-Tag: 2.49.0~31^2~4
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=f11e2b51f4bb09a3e5059aea93f3a253e808cc88;p=graphviz

eval: avoid sfprintf in integer-to-string dynamic

Instead of constructing a string in the `tmp` buffer and then eventually
allocating vmalloc space to copy this into, we can simply compute the number of
bytes in advance, allocate vmalloc space, and then directly emit the output into
the vmalloc buffer. Related to #1873, #1998.
---

diff --git a/lib/expr/exeval.c b/lib/expr/exeval.c
index 0bc040ff7..ea7fc9e33 100644
--- a/lib/expr/exeval.c
+++ b/lib/expr/exeval.c
@@ -1787,11 +1787,12 @@ eval(Expr_t* ex, Exnode_t* expr, void* env)
 				tmp.data.constant.value.string = str;
 			}
 			else if ((*ex->disc->convertf)(ex, &tmp, STRING, expr->data.operand.right ? expr->data.operand.right->data.variable.symbol : (Exid_t*)0, 0, ex->disc)) {
+				char *str = NULL;
 				if (expr->data.operand.left->type == UNSIGNED)
-					sfprintf(ex->tmp, "%I*u", sizeof(v.integer), v.integer);
+					str = exprintf(ex->ve, "%llu", (unsigned long long)v.integer);
 				else
-					sfprintf(ex->tmp, "%I*d", sizeof(v.integer), v.integer);
-				tmp.data.constant.value.string =  exstash(ex->tmp, ex->ve);
+					str = exprintf(ex->ve, "%lld", (long long)v.integer);
+				tmp.data.constant.value.string = str;
 			}
 			tmp.type = STRING;
 			return tmp.data.constant.value;