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authorCan Celik <ogulcancelik@gmail.com>2026-04-04 19:22:04 +0300
committerCan Celik <ogulcancelik@gmail.com>2026-04-05 01:23:06 +0300
commit41dd733ca7123c9ac4bfc6c781697a660e95b052 (patch)
tree3fc91815ca139ef2e0b281bba0abda4ef15175f4 /vendor/libghostty-vt/pkg/afl++/afl.c
parent55c138263e190a1e79d4b997bfb9397306c0ec1f (diff)
feat: finish ghostty pane backend integration
Diffstat (limited to 'vendor/libghostty-vt/pkg/afl++/afl.c')
-rw-r--r--vendor/libghostty-vt/pkg/afl++/afl.c141
1 files changed, 141 insertions, 0 deletions
diff --git a/vendor/libghostty-vt/pkg/afl++/afl.c b/vendor/libghostty-vt/pkg/afl++/afl.c
new file mode 100644
index 00000000..61eb12c4
--- /dev/null
+++ b/vendor/libghostty-vt/pkg/afl++/afl.c
@@ -0,0 +1,141 @@
+#include <limits.h>
+#include <signal.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+// AFL++ fuzzer harness for Zig fuzz targets.
+//
+// This file is the C "glue" that connects AFL++'s runtime to Zig-defined
+// fuzz test functions. We can't use AFL++'s compiler wrappers (afl-clang,
+// afl-gcc) because the code under test is compiled with Zig, so we manually
+// expand the AFL macros (__AFL_INIT, __AFL_LOOP, __AFL_FUZZ_INIT, etc.) and
+// wire up the sanitizer coverage symbols ourselves.
+
+// To ensure checks are not optimized out it is recommended to disable
+// code optimization for the fuzzer harness main()
+#pragma clang optimize off
+#pragma GCC optimize("O0")
+
+// Zig-exported entry points. zig_fuzz_init() performs one-time setup and
+// zig_fuzz_test() runs one fuzz iteration on the given input buffer.
+// The Zig object should export these.
+void zig_fuzz_init();
+void zig_fuzz_test(unsigned char*, size_t);
+
+// Linker-provided symbols marking the boundaries of the __sancov_guards
+// section. These must be declared extern so the linker provides the actual
+// section boundaries from the instrumented code, rather than creating new
+// variables that shadow them. On macOS (Mach-O), the linker uses a different
+// naming convention for section boundaries than Linux (ELF), so we use asm
+// labels to reference them.
+#ifdef __APPLE__
+extern uint32_t __start___sancov_guards __asm(
+ "section$start$__DATA$__sancov_guards");
+extern uint32_t __stop___sancov_guards __asm(
+ "section$end$__DATA$__sancov_guards");
+#else
+extern uint32_t __start___sancov_guards;
+extern uint32_t __stop___sancov_guards;
+#endif
+
+// Provided by afl-compiler-rt; initializes the guard array used by
+// SanitizerCoverage's trace-pc-guard instrumentation mode.
+void __sanitizer_cov_trace_pc_guard_init(uint32_t*, uint32_t*);
+
+// Stubs for sanitizer coverage callbacks that the Zig-compiled code references
+// but AFL's runtime (afl-compiler-rt) does not provide. Without these, linking
+// would fail with undefined symbol errors.
+__attribute__((visibility("default"))) __attribute__((
+ tls_model("initial-exec"))) _Thread_local uintptr_t __sancov_lowest_stack;
+void __sanitizer_cov_trace_pc_indir() {}
+void __sanitizer_cov_8bit_counters_init() {}
+void __sanitizer_cov_pcs_init() {}
+
+// Manual expansion of __AFL_FUZZ_INIT().
+//
+// Enables shared-memory fuzzing: AFL++ writes test cases directly into
+// shared memory (__afl_fuzz_ptr) instead of passing them via stdin, which
+// is much faster. When not running under AFL++ (e.g. standalone execution),
+// __afl_fuzz_ptr will be NULL and we fall back to reading from stdin into
+// __afl_fuzz_alt (a 1 MB static buffer).
+int __afl_sharedmem_fuzzing = 1;
+extern __attribute__((visibility("default"))) unsigned int* __afl_fuzz_len;
+extern __attribute__((visibility("default"))) unsigned char* __afl_fuzz_ptr;
+unsigned char __afl_fuzz_alt[1048576];
+unsigned char* __afl_fuzz_alt_ptr = __afl_fuzz_alt;
+
+int main(int argc, char** argv) {
+ // Tell AFL's coverage runtime about our guard section so it can track
+ // which edges in the instrumented Zig code have been hit.
+ __sanitizer_cov_trace_pc_guard_init(&__start___sancov_guards,
+ &__stop___sancov_guards);
+
+ // Manual expansion of __AFL_INIT() — deferred fork server mode.
+ //
+ // The magic string "##SIG_AFL_DEFER_FORKSRV##" is embedded in the binary
+ // so AFL++'s tooling can detect that this harness uses deferred fork
+ // server initialization. The `volatile` + `used` attributes prevent the
+ // compiler/linker from stripping it. We then call __afl_manual_init() to
+ // start the fork server at this point (after our setup) rather than at
+ // the very beginning of main().
+ static volatile const char* _A __attribute__((used, unused));
+ _A = (const char*)"##SIG_AFL_DEFER_FORKSRV##";
+#ifdef __APPLE__
+ __attribute__((visibility("default"))) void _I(void) __asm__(
+ "___afl_manual_init");
+#else
+ __attribute__((visibility("default"))) void _I(void) __asm__(
+ "__afl_manual_init");
+#endif
+ _I();
+
+ zig_fuzz_init();
+
+ // Manual expansion of __AFL_FUZZ_TESTCASE_BUF.
+ // Use shared memory buffer if available, otherwise fall back to the
+ // static buffer (for standalone/non-AFL execution).
+ unsigned char* buf = __afl_fuzz_ptr ? __afl_fuzz_ptr : __afl_fuzz_alt_ptr;
+
+ // Manual expansion of __AFL_LOOP(UINT_MAX) — persistent mode loop.
+ //
+ // Persistent mode keeps the process alive across many test cases instead
+ // of fork()'ing for each one, dramatically improving throughput. The magic
+ // string "##SIG_AFL_PERSISTENT##" signals to AFL++ that this binary
+ // supports persistent mode. __afl_persistent_loop() returns non-zero
+ // while there are more inputs to process.
+ //
+ // When connected to AFL++, we loop UINT_MAX times (essentially forever,
+ // AFL will restart us periodically). When running standalone, we loop
+ // once so the harness can be used for manual testing/reproduction.
+ while (({
+ static volatile const char* _B __attribute__((used, unused));
+ _B = (const char*)"##SIG_AFL_PERSISTENT##";
+ extern __attribute__((visibility("default"))) int __afl_connected;
+#ifdef __APPLE__
+ __attribute__((visibility("default"))) int _L(unsigned int) __asm__(
+ "___afl_persistent_loop");
+#else
+ __attribute__((visibility("default"))) int _L(unsigned int) __asm__(
+ "__afl_persistent_loop");
+#endif
+ _L(__afl_connected ? UINT_MAX : 1);
+ })) {
+ // Manual expansion of __AFL_FUZZ_TESTCASE_LEN.
+ // In shared-memory mode, the length is provided directly by AFL++.
+ // In standalone mode, we read from stdin into the fallback buffer.
+ int len =
+ __afl_fuzz_ptr ? *__afl_fuzz_len
+ : (*__afl_fuzz_len = read(0, __afl_fuzz_alt_ptr, 1048576)) == 0xffffffff
+ ? 0
+ : *__afl_fuzz_len;
+
+ if (len >= 0) {
+ zig_fuzz_test(buf, len);
+ }
+ }
+
+ return 0;
+}