RNA: support extracting names from paths without allocating memory

Support extracting identifiers RNA paths into fixed size buffer
since the maximum size of the identifier is known all cases.

- Add BLI_str_unescape_ex to support limiting the destination buffer.
- Add BLI_str_quoted_substr to copy values into a fixed size buffer.

2 files changed, 15 insertions, 15 deletions

diff --git a/source/blender/blenkernel/intern/action_bones.cc b/source/blender/blenkernel/intern/action_bones.cc
index b8d185e6a81..1f2b7360b70 100644
--- a/source/blender/blenkernel/intern/action_bones.cc
+++ b/source/blender/blenkernel/intern/action_bones.cc
@@ -28,6 +28,7 @@
 
 #include "DNA_action_types.h"
 #include "DNA_anim_types.h"
+#include "DNA_armature_types.h"
 
 #include "MEM_guardedalloc.h"
 
@@ -36,12 +37,11 @@ namespace blender::bke {
 void BKE_action_find_fcurves_with_bones(const bAction *action, FoundFCurveCallback callback)
 {
   LISTBASE_FOREACH (FCurve *, fcu, &action->curves) {
-    char *bone_name = BLI_str_quoted_substrN(fcu->rna_path, "pose.bones[");
-    if (!bone_name) {
+    char bone_name[MAXBONENAME];
+    if (!BLI_str_quoted_substr(fcu->rna_path, "pose.bones[", bone_name, sizeof(bone_name))) {
       continue;
     }
     callback(fcu, bone_name);
-    MEM_freeN(bone_name);
   }
 }
 
diff --git a/source/blender/blenkernel/intern/fcurve.c b/source/blender/blenkernel/intern/fcurve.c
index fb6cd5871f4..8e9c504dcbf 100644
--- a/source/blender/blenkernel/intern/fcurve.c
+++ b/source/blender/blenkernel/intern/fcurve.c
@@ -346,30 +346,30 @@ int BKE_fcurves_filter(ListBase *dst, ListBase *src, const char *dataPrefix, con
     return 0;
   }
 
+  const size_t quotedName_size = strlen(dataName) + 1;
+  char *quotedName = alloca(quotedName_size);
+
   /* Search each F-Curve one by one. */
   for (fcu = src->first; fcu; fcu = fcu->next) {
     /* Check if quoted string matches the path. */
     if (fcu->rna_path == NULL) {
       continue;
     }
-
-    char *quotedName = BLI_str_quoted_substrN(fcu->rna_path, dataPrefix);
-    if (quotedName == NULL) {
+    /* Skipping names longer than `quotedName_size` is OK since we're after an exact match. */
+    if (!BLI_str_quoted_substr(fcu->rna_path, dataPrefix, quotedName, quotedName_size)) {
+      continue;
+    }
+    if (!STREQ(quotedName, dataName)) {
       continue;
     }
 
     /* Check if the quoted name matches the required name. */
-    if (STREQ(quotedName, dataName)) {
-      LinkData *ld = MEM_callocN(sizeof(LinkData), __func__);
-
-      ld->data = fcu;
-      BLI_addtail(dst, ld);
+    LinkData *ld = MEM_callocN(sizeof(LinkData), __func__);
 
-      matches++;
-    }
+    ld->data = fcu;
+    BLI_addtail(dst, ld);
 
-    /* Always free the quoted string, since it needs freeing. */
-    MEM_freeN(quotedName);
+    matches++;
   }
   /* Return the number of matches. */
   return matches;