Allow to choose the log level at runtime

3 files changed, 49 insertions, 8 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index bab9a2f..e592a24 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,8 @@
 # Changelog
 
+## 0.2.0 (Upcoming release)
+- Allow to choose the log level at runtime
+
 ## 0.1.0 (2024-05-20)
 - Add LSTD_ASSERT macros
 - Add bitset module
diff --git a/src/lisiblestd/log.c b/src/lisiblestd/log.c
index a28d202..2548fd5 100644
--- a/src/lisiblestd/log.c
+++ b/src/lisiblestd/log.c
@@ -1,18 +1,53 @@
 #include "log.h"
+#include <stdlib.h>
+#include <string.h>
+
+LogLevel lstd_log_level = LogLevel_Info;
+
+void lstd_log_init(void) {
+  const char *log_level_str = getenv("LSTD_LOG");
+  if (log_level_str) {
+    lstd_log_level = log_level_from_str(log_level_str);
+  }
+}
+
+const char *LSTD_LOG_LEVEL_STR_TRACE = "TRACE";
+const char *LSTD_LOG_LEVEL_STR_DEBUG = "DEBUG";
+const char *LSTD_LOG_LEVEL_STR_WARN = "WARN";
+const char *LSTD_LOG_LEVEL_STR_ERROR = "ERROR";
+const char *LSTD_LOG_LEVEL_STR_INFO = "INFO";
 
 const char *log_level_to_str(LogLevel log_level) {
   switch (log_level) {
   case LogLevel_Trace:
-    return "TRACE";
+    return LSTD_LOG_LEVEL_STR_TRACE;
   case LogLevel_Debug:
-    return "DEBUG";
+    return LSTD_LOG_LEVEL_STR_DEBUG;
   case LogLevel_Warn:
-    return "WARN";
+    return LSTD_LOG_LEVEL_STR_WARN;
   case LogLevel_Error:
-    return "ERROR";
+    return LSTD_LOG_LEVEL_STR_ERROR;
   case LogLevel_Info:
   default:
-    return "INFO";
+    return LSTD_LOG_LEVEL_STR_INFO;
     break;
   }
 }
+
+LogLevel log_level_from_str(const char *str) {
+  if (strncmp(str, LSTD_LOG_LEVEL_STR_TRACE,
+              strlen(LSTD_LOG_LEVEL_STR_TRACE)) == 0) {
+    return LogLevel_Trace;
+  } else if (strncmp(str, LSTD_LOG_LEVEL_STR_DEBUG,
+                     strlen(LSTD_LOG_LEVEL_STR_DEBUG)) == 0) {
+    return LogLevel_Debug;
+  } else if (strncmp(str, LSTD_LOG_LEVEL_STR_WARN,
+                     strlen(LSTD_LOG_LEVEL_STR_WARN)) == 0) {
+    return LogLevel_Warn;
+  } else if (strncmp(str, LSTD_LOG_LEVEL_STR_ERROR,
+                     strlen(LSTD_LOG_LEVEL_STR_ERROR)) == 0) {
+    return LogLevel_Error;
+  }
+
+  return LogLevel_Info;
+}
diff --git a/src/lisiblestd/log.h b/src/lisiblestd/log.h
index e44dd7e..1fa6ad3 100644
--- a/src/lisiblestd/log.h
+++ b/src/lisiblestd/log.h
@@ -12,11 +12,12 @@ typedef enum {
   LogLevel_Error,
   LogLevel_Info
 } LogLevel;
-#define LSTD_LOG_LEVEL LogLevel_Trace
+
+extern LogLevel lstd_log_level;
 
 #define LOG0(log_level, msg)                                                   \
   do {                                                                         \
-    if (LSTD_LOG_LEVEL <= log_level) {                                         \
+    if (lstd_log_level <= log_level) {                                         \
       fprintf(stderr, LSTD_LOG_PREFIX "%s\n", log_level_to_str(log_level),     \
               __FILE__, __LINE__, msg);                                        \
     }                                                                          \
@@ -29,7 +30,7 @@ typedef enum {
 
 #define LOG(log_level, fmt, ...)                                               \
   do {                                                                         \
-    if (LSTD_LOG_LEVEL <= log_level) {                                         \
+    if (lstd_log_level <= log_level) {                                         \
       fprintf(stderr, LSTD_LOG_PREFIX fmt "\n", log_level_to_str(log_level),   \
               __FILE__, __LINE__, __VA_ARGS__);                                \
     }                                                                          \
@@ -40,6 +41,8 @@ typedef enum {
 #define LOG_ERROR(fmt, ...) LOG(LogLevel_Error, fmt, __VA_ARGS__)
 #define LOG_INFO(fmt, ...) LOG(LogLevel_Info, fmt, __VA_ARGS__)
 
+void lstd_log_init(void);
 const char *log_level_to_str(LogLevel log_level);
+LogLevel log_level_from_str(const char *str);
 
 #endif // LSTD_LOG_H