From cc660f8609fd2f8a2a753c4fc1c3e18e6713847c Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kacper=20Michaj=C5=82ow?= <kasper93@gmail.com>
Date: Wed, 6 Aug 2025 02:25:21 +0200
Subject: [PATCH] fuzzers: set fontconfig sysroot

Allows to specify custom fontconfig sysroot. Useful for fuzzing
environments where we might use specific config, font or the system wide
config is not available.
---
 fuzzers/common.h                 | 7 +++++++
 fuzzers/fuzzer_load.c            | 2 ++
 fuzzers/fuzzer_loadfile_direct.c | 2 ++
 fuzzers/fuzzer_options_parser.c  | 2 ++
 fuzzers/fuzzer_set_property.c    | 2 ++
 5 files changed, 15 insertions(+)

diff --git a/fuzzers/common.h b/fuzzers/common.h
index f3160b957c..e8d32fa76b 100644
--- a/fuzzers/common.h
+++ b/fuzzers/common.h
@@ -48,6 +48,13 @@ static inline bool str_startswith(const char *str, size_t str_len,
     return !memcmp(str, prefix, prefix_len);
 }
 
+static inline void set_fontconfig_sysroot(void)
+{
+#ifdef MPV_FONTCONFIG_SYSROOT
+    setenv("FONTCONFIG_SYSROOT", MPV_STRINGIFY(MPV_FONTCONFIG_SYSROOT), 1);
+#endif
+}
+
 #ifndef PLAYBACK_TIME_LIMIT
 #define PLAYBACK_TIME_LIMIT 5
 #endif
diff --git a/fuzzers/fuzzer_load.c b/fuzzers/fuzzer_load.c
index db3b192075..d1aa7f215b 100644
--- a/fuzzers/fuzzer_load.c
+++ b/fuzzers/fuzzer_load.c
@@ -64,6 +64,8 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     if (sprintf(filename, "fd://%d", fd) <= 5)
         exit(1);
 
+    set_fontconfig_sysroot();
+
     mpv_handle *ctx = mpv_create();
     if (!ctx)
         exit(1);
diff --git a/fuzzers/fuzzer_loadfile_direct.c b/fuzzers/fuzzer_loadfile_direct.c
index f12134f22f..9efd4ab964 100644
--- a/fuzzers/fuzzer_loadfile_direct.c
+++ b/fuzzers/fuzzer_loadfile_direct.c
@@ -39,6 +39,8 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
         return 0;
 #endif
 
+    set_fontconfig_sysroot();
+
     mpv_handle *ctx = mpv_create();
     if (!ctx)
         exit(1);
diff --git a/fuzzers/fuzzer_options_parser.c b/fuzzers/fuzzer_options_parser.c
index c759a099ec..64add540eb 100644
--- a/fuzzers/fuzzer_options_parser.c
+++ b/fuzzers/fuzzer_options_parser.c
@@ -56,6 +56,8 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     }
     opts[count] = NULL;
 
+    set_fontconfig_sysroot();
+
     mpv_handle *ctx = mpv_create();
     if (!ctx)
         exit(1);
diff --git a/fuzzers/fuzzer_set_property.c b/fuzzers/fuzzer_set_property.c
index f5c17c342a..8faf9065e9 100644
--- a/fuzzers/fuzzer_set_property.c
+++ b/fuzzers/fuzzer_set_property.c
@@ -54,6 +54,8 @@ int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)
     if (!name_len || name_len != size - value_len - 1)
         return 0;
 
+    set_fontconfig_sysroot();
+
     mpv_handle *ctx = mpv_create();
     if (!ctx)
         exit(1);