[Issue #4] Added a logging interface

Makefile.am

@@ -28,6 +28,7 @@ subdirinclude_HEADERS = \
 	include/criterion/criterion.h \
 	include/criterion/event.h \
 	include/criterion/hooks.h \
+	include/criterion/logging.h \
 	include/criterion/stats.h
 
 libcriterion_la_SOURCES = \
@@ -41,4 +42,5 @@ libcriterion_la_SOURCES = \
 	src/process.h \
 	src/stats.c \
 	src/stats.h \
+	src/logging.c \
 	src/main.c

include/criterion/common.h

@@ -27,4 +27,10 @@
 # define SECTION_(Name) __attribute__((section(Name)))
 # define UNUSED __attribute__((unused))
 
+# ifdef __GNUC__
+#  define FORMAT(Archetype, Index, Ftc) __attribute__((format(Archetype, Index, Ftc)))
+# else
+#  define FORMAT(Archetype, Index, Ftc)
+# endif
+
 #endif /* !CRITERION_COMMON_H_ */

include/criterion/logging.h

@@ -0,0 +1,19 @@
+#ifndef CRITERION_LOGGING_H_
+# define CRITERION_LOGGING_H_
+
+#include "common.h"
+
+enum criterion_logging_level {
+    CRITERION_INFO = 1,
+    CRITERION_IMPORTANT,
+};
+
+extern enum criterion_logging_level logging_threshold;
+
+FORMAT(printf, 2, 3)
+void criterion_log(enum criterion_logging_level level, const char *msg, ...);
+
+# define criterion_info(...) criterion_log(CRITERION_INFO, __VA_ARGS__)
+# define criterion_important(...) criterion_log(CRITERION_IMPORTANT, __VA_ARGS__)
+
+#endif /* !CRITERION_LOGGING_H_ */

src/logging.c

@@ -0,0 +1,16 @@
+#include <stdio.h>
+#include <stdarg.h>
+#include "criterion/logging.h"
+
+enum criterion_logging_level logging_threshold = CRITERION_IMPORTANT;
+
+void criterion_log(enum criterion_logging_level level, const char *msg, ...) {
+    va_list args;
+
+    if (level < logging_threshold)
+        return;
+
+    va_start(args, msg);
+    vfprintf(stderr, msg, args);
+    va_end(args);
+}

src/main.c

@@ -1,5 +1,34 @@
+#define _GNU_SOURCE
 #include <criterion/criterion.h>
+#include <criterion/logging.h>
+#include <stdio.h>
+#include <getopt.h>
+
+# define USAGE                                          \
+    "usage: %s OPTIONS\n"                               \
+    "options: \n"                                       \
+    "    -h or --help: prints this message\n"           \
+    "    --verbose [level]: sets verbosity to level\n"
+
+int print_usage(char *progname) {
+    fprintf(stderr, USAGE, progname);
+    return 0;
+}
+
+int main(int argc, char *argv[]) {
+    static struct option opts[] = {
+        {"verbose", optional_argument,  0, 'v'},
+        {"help",    no_argument,        0, 'h'},
+        {0,         0,                  0,  0 }
+    };
+
+    for (int c; (c = getopt_long(argc, argv, "h", opts, NULL)) != -1;) {
+        switch (c) {
+            case 'v': logging_threshold = atoi(optarg ?: "1"); break;
+            case 'h':
+            default : return print_usage(argv[0]);
+        }
+    }
 
-int main(void) {
     return criterion_run_all_tests();
 }

src/report.c

@@ -24,6 +24,7 @@
 #include <stdio.h>
 #include "criterion/criterion.h"
 #include "criterion/stats.h"
+#include "criterion/logging.h"
 #include "report.h"
 
 #define IMPL_CALL_REPORT_HOOKS(Kind)                        \
@@ -49,32 +50,40 @@ IMPL_CALL_REPORT_HOOKS(POST_FINI);
 IMPL_CALL_REPORT_HOOKS(POST_EVERYTHING);
 
 ReportHook(PRE_INIT)(struct criterion_test *test) {
-    fprintf(stderr, "%s::%s: RUNNING\n", test->category, test->name);
+    criterion_info("%s::%s: RUNNING\n", test->category, test->name);
 }
 
 ReportHook(POST_TEST)(struct criterion_test_stats *stats) {
-    fprintf(stderr, "%s::%s: %s\n", stats->test->category, stats->test->name, stats->failed ? "FAILURE" : "SUCCESS");
+    criterion_log(stats->failed ? CRITERION_IMPORTANT : CRITERION_INFO,
+            "%s::%s: %s\n",
+            stats->test->category,
+            stats->test->name,
+            stats->failed ? "FAILURE" : "SUCCESS");
 }
 
 ReportHook(PRE_TEST)() {}
 ReportHook(POST_FINI)() {}
 
 ReportHook(PRE_EVERYTHING)() {}
 ReportHook(POST_EVERYTHING)(struct criterion_global_stats *stats) {
-    fprintf(stderr, "Synthesis: %lu tests were run. %lu passed, %lu failed (with %lu crashes)\n", stats->nb_tests, stats->tests_passed, stats->tests_failed, stats->tests_crashed);
+    criterion_important("Synthesis: %lu tests were run. %lu passed, %lu failed (with %lu crashes)\n",
+            stats->nb_tests,
+            stats->tests_passed,
+            stats->tests_failed,
+            stats->tests_crashed);
 }
 
 ReportHook(ASSERT)(struct criterion_assert_stats *stats) {
     if (!stats->passed) {
-        fprintf(stderr, "\t%s:%d: Assertion failed: %s\n",
+        criterion_important("%s:%d: Assertion failed: %s\n",
                 stats->file,
                 stats->line,
                 *stats->message ? stats->message : stats->condition);
     }
 }
 
 ReportHook(TEST_CRASH)(struct criterion_test_stats *stats) {
-    fprintf(stderr, "\tUnexpected signal after %s:%u!\n%s::%s: FAILURE (CRASH!)\n",
+    criterion_important("Unexpected signal after %s:%u!\n%s::%s: FAILURE (CRASH!)\n",
             stats->file,
             stats->progress,
             stats->test->category,