cli: Create BST_VERBOSITY to enable/disable warnings

err.c

@@ -26,6 +26,35 @@ void (*err_exit)(int) = exit;
 const char *err_line_ending = "\n";
 int err_flags = 0;
 
+/* Parse the BST_VERBOSITY environment variable to determine the requested
+   verbosity. Higher numbers are associated with more verbosity, with 9
+   being the most verbose and 0 being the least verbose. The default
+   verbosity level is 1. */
+
+noreturn void err(int eval, const char *fmt, ...);
+static int parsedverbosity(void)
+{
+	char *pszVerbosity = getenv("BST_VERBOSITY");
+	if (pszVerbosity == NULL) {
+		return 1;
+	}
+	char *endPtr;
+	int iVerbosity = strtol(pszVerbosity, &endPtr, 10);
+	if (*endPtr != '\0') {
+        err(2, "un-parsable value of BST_VERBOSITY");
+	}
+	return iVerbosity;
+}
+
+void init_logverbosity(void)
+{
+	int iVerbosity = parsedverbosity();
+
+	if (iVerbosity >= 1) {
+		err_flags |= ERR_VERBOSE;
+	}
+}
+
 /* fdprintf and vfdprintf are fork-safe versions of fprintf and vfprintf. */
 
 static void vfdprintf(int fd, const char *fmt, va_list vl)
@@ -64,6 +93,9 @@ static void vwarnsyslog(int errcode, const char *fmt, va_list vl)
 
 void vwarn(const char *fmt, va_list vl)
 {
+    if (!(err_flags & ERR_VERBOSE)) {
+        return;
+    }
 	if (err_flags & ERR_USE_SYSLOG) {
 		vwarnsyslog(errno, fmt, vl);
 		return;
@@ -75,6 +107,9 @@ void vwarn(const char *fmt, va_list vl)
 
 void vwarnx(const char *fmt, va_list vl)
 {
+    if (!(err_flags & ERR_VERBOSE)) {
+        return;
+    }
 	if (err_flags & ERR_USE_SYSLOG) {
 		vwarnsyslog(0, fmt, vl);
 		return;

errutil.h

@@ -9,10 +9,13 @@
 
 enum {
 	ERR_USE_SYSLOG = 1,
+
+	ERR_VERBOSE = 2,
 };
 
 extern void (*err_exit)(int);
 extern const char *err_line_ending;
+void init_logverbosity();
 extern int err_flags;
 
 #endif /* !ERRUTIL_H */

main.c

@@ -24,6 +24,7 @@
 #include "capable.h"
 #include "compat.h"
 #include "enter.h"
+#include "errutil.h"
 #include "kvlist.h"
 #include "util.h"
 #include "path.h"
@@ -263,6 +264,7 @@ int usage(int error, char *argv0)
 
 int main(int argc, char *argv[], char *envp[])
 {
+    init_logverbosity();
 	init_capabilities();
 
 	static struct entry_settings opts;