From 33e0ee7162f439817e09d3a473cf314e1c4c6512 Mon Sep 17 00:00:00 2001
From: Arseny Kapoulkine <arseny.kapoulkine@gmail.com>
Date: Sun, 13 Aug 2023 10:08:29 -0700
Subject: [PATCH] Trim trailing whitespace for names

Some .obj files have extra whitespace after usemtl and other statements;
this may interfere with parsing, for example by adding a space to the
material name which can result in inability to find it in .mtl file.

For consistency, we replace all uses of is_end_of_name with skip_name
that handles this by leaving trailing whitespace alone. It will be
skipped in the parsing flow when we skip the newline, which is similar
to the behavior of trailing whitespace after numeric data (which
parse_float/int leave alone).
---
 fast_obj.h | 50 ++++++++++++++++++++++++--------------------------
 1 file changed, 24 insertions(+), 26 deletions(-)

diff --git a/fast_obj.h b/fast_obj.h
index b39c0f6..777f8dc 100644
--- a/fast_obj.h
+++ b/fast_obj.h
@@ -297,7 +297,7 @@ void* file_open(const char* path, void* user_data)
 static
 void file_close(void* file, void* user_data)
 {
-	FILE* f;
+    FILE* f;
     (void)(user_data);
     
     f = (FILE*)(file);
@@ -308,7 +308,7 @@ void file_close(void* file, void* user_data)
 static
 size_t file_read(void* file, void* dst, size_t bytes, void* user_data)
 {
-	FILE* f;
+    FILE* f;
     (void)(user_data);
     
     f = (FILE*)(file);
@@ -323,7 +323,7 @@ unsigned long file_size(void* file, void* user_data)
     long p;
     long n;
     (void)(user_data);
-	
+        
     f = (FILE*)(file);
 
     p = ftell(f);
@@ -413,12 +413,6 @@ int is_whitespace(char c)
     return (c == ' ' || c == '\t' || c == '\r');
 }
 
-static
-int is_end_of_name(char c)
-{
-    return (c == '\t' || c == '\r' || c == '\n');
-}
-
 static
 int is_newline(char c)
 {
@@ -440,6 +434,21 @@ int is_exponent(char c)
 }
 
 
+static
+const char* skip_name(const char* ptr)
+{
+    const char* s = ptr;
+
+    while (!is_newline(*ptr))
+        ptr++;
+
+    while (ptr > s && is_whitespace(*(ptr - 1)))
+        ptr--;
+
+    return ptr;
+}
+
+
 static
 const char* skip_whitespace(const char* ptr)
 {
@@ -791,9 +800,7 @@ const char* parse_object(fastObjData* data, const char* ptr)
     ptr = skip_whitespace(ptr);
 
     s = ptr;
-    while (!is_end_of_name(*ptr))
-        ptr++;
-
+    ptr = skip_name(ptr);
     e = ptr;
 
     flush_object(data);
@@ -813,9 +820,7 @@ const char* parse_group(fastObjData* data, const char* ptr)
     ptr = skip_whitespace(ptr);
 
     s = ptr;
-    while (!is_end_of_name(*ptr))
-        ptr++;
-
+    ptr = skip_name(ptr);
     e = ptr;
 
     flush_group(data);
@@ -894,9 +899,7 @@ const char* parse_usemtl(fastObjData* data, const char* ptr)
 
     /* Parse the material name */
     s = ptr;
-    while (!is_end_of_name(*ptr))
-        ptr++;
-
+    ptr = skip_name(ptr);
     e = ptr;
 
     /* Find an existing material with the same name */
@@ -992,9 +995,7 @@ const char* read_map(fastObjData* data, const char* ptr, fastObjTexture* map)
 
     /* Read name */
     s = ptr;
-    while (!is_end_of_name(*ptr))
-        ptr++;
-
+    ptr = skip_name(ptr);
     e = ptr;
 
     name = string_copy(s, e);
@@ -1068,8 +1069,7 @@ int read_mtllib(fastObjData* data, void* file, const fastObjCallbacks* callbacks
                     p++;
 
                 s = p;
-                while (!is_end_of_name(*p))
-                    p++;
+                p = skip_name(p);
 
                 mtl.name = string_copy(s, p);
             }
@@ -1211,9 +1211,7 @@ const char* parse_mtllib(fastObjData* data, const char* ptr, const fastObjCallba
     ptr = skip_whitespace(ptr);
 
     s = ptr;
-    while (!is_end_of_name(*ptr))
-        ptr++;
-
+    ptr = skip_name(ptr);
     e = ptr;
 
     lib = string_concat(data->base, s, e);