From c3a63f3e3c19225524b7ff7168a4385b44393318 Mon Sep 17 00:00:00 2001
From: Johannes Stoelp <johannes.stoelp@gmail.com>
Date: Tue, 10 Sep 2024 20:41:22 +0200
Subject: minor cleanups

---
 README.md |  4 ++--
 bt.c      | 28 +++++++++++++---------------
 2 files changed, 15 insertions(+), 17 deletions(-)

diff --git a/README.md b/README.md
index f6a0497..2e691d1 100644
--- a/README.md
+++ b/README.md
@@ -31,8 +31,8 @@ cc -o libbt.so bt.c -shared -fPIC -ldl
 cc -o raise1 example/raise1.c -rdynamic
 LD_PRELOAD=./libbt.so ./raise1
 
-[INFO:BT]: installed signal handler
-[INFO:BT]: caught signal 11
+[BT:INFO]: installed signal handler
+[BT:INFO]: caught signal 11
 # 0 [  0x7f53b9e203f4] /usr/lib/libc.so.6+0x963f4
 # 1 [  0x7f53b9dc7120] gsignal+0x20 /usr/lib/libc.so.6+0x3d100
 # 2 [  0x55748166c147] foo+0xe raise1+0x1139
diff --git a/bt.c b/bt.c
index 4a2c743..d51d35c 100644
--- a/bt.c
+++ b/bt.c
@@ -33,16 +33,14 @@
 
 #include <unwind.h>  // from gcc, clang
 
-#define LOG(fmt, ...)                                              \
-  do {                                                             \
-    char buf[1024];                                                \
-    int cnt = snprintf(buf, sizeof(buf), fmt "\n", ##__VA_ARGS__); \
-    write(STDERR_FILENO, buf, cnt);                                \
+#define LOG(fmt, ...)                         \
+  do {                                        \
+    fprintf(stderr, fmt "\n", ##__VA_ARGS__); \
   } while (0)
 
-#define INFO(fmt, ...) LOG("[\e[0;32mINFO:BT\e[0m]: " fmt, ##__VA_ARGS__)
-#define WARN(fmt, ...) LOG("[\e[0;33mWARN:BT\e[0m]: " fmt, ##__VA_ARGS__)
-#define FAIL(fmt, ...) LOG("[\e[0;31mFAIL:BT\e[0m]: " fmt, ##__VA_ARGS__)
+#define INFO(fmt, ...) LOG("[BT:\e[0;32mINFO\e[0m]: " fmt, ##__VA_ARGS__)
+#define WARN(fmt, ...) LOG("[BT:\e[0;33mWARN\e[0m]: " fmt, ##__VA_ARGS__)
+#define FAIL(fmt, ...) LOG("[BT:\e[0;31mFAIL\e[0m]: " fmt, ##__VA_ARGS__)
 
 // -- UNWIND HANDLER -----------------------------------------------------------
 
@@ -109,16 +107,16 @@ static void libbt_report(int sig, siginfo_t* info, void* ucontext) {
     OLD.sa_handler(sig);
   }
 
-  const char* noexit = getenv("BT_NOEXIT");
+  const char* noexit = getenv("LIBBT_NOEXIT");
   if (noexit && noexit[0] == '1') {
     return;
   }
-  INFO("exit after catching signal, set BT_NOEXIT=1 to keep running");
+  INFO("exit after catching signal, set LIBBT_NOEXIT=1 to keep running");
   exit(42);
 }
 
 static void* libbt_install_sigstack() {
-  const size_t STACK_SIZE = 8192;
+  const size_t STACK_SIZE = 8 * MINSIGSTKSZ;
 
   void* sp = malloc(STACK_SIZE);
   if (sp == NULL) {
@@ -149,10 +147,10 @@ static int libbt_install_sighandler() {
 
 // -- THREAD HANDLING ----------------------------------------------------------
 
-int (*NEXT_PTHREAD_CREATE)(pthread_t*,
-                           const pthread_attr_t*,
-                           void* (*)(void*),
-                           void*);
+static int (*NEXT_PTHREAD_CREATE)(pthread_t*,
+                                  const pthread_attr_t*,
+                                  void* (*)(void*),
+                                  void*);
 
 static int THREAD_CREATE_SIGSTACK = 0;
 
-- 
cgit v1.2.3