portable_basename.* + clock_hr_microsec.*: split and improve

c-programming/benchmarking/clock_hr_microsec.c

@@ -0,0 +1,133 @@
+/*
+ * clock_hr_microsec.c
+ *
+ * A small library to measure execution time of code as precisely as possible.
+ *
+ * TODO: Use fixed point arithmetics
+ *
+ * Author: Intel A80486DX2-66
+ * License: Unlicense
+ */
+
+#include "clock_hr_microsec.h"
+
+// macros
+#if defined(SYS_NT)
+static LONGLONG QPF_frequency;
+
+# define WinAPI_perror_COMMON_MACRO \
+      fprintf(stderr, "%s: %lu, %s", s, errorCode, errorString)
+# define CLOCK_HR_DIFFTIME_MS(t2, t1)                                         \
+      (((clock_hr_microsec_t) ((t2) - (t1))) /                                \
+       ((clock_hr_microsec_t) QPF_frequency))
+
+#elif defined(SYS_UNIX)
+# define CLOCK_HR_DIFFTIME_MS(t2, t1)                                         \
+      ((t2) - (t1))
+
+#else
+# define CLOCK_HR_DIFFTIME_MS(t2, t1)                                         \
+      ((clock_hr_microsec_t) ((t2) - (t1)) * 1000000.L) /                             \
+      ((clock_hr_microsec_t) CLOCKS_PER_SEC)
+
+#endif
+
+// function implementations
+void clock_hr_microsec_init(void) {
+# ifdef SYS_NT
+	// set console output code page to the native one
+	SetConsoleOutputCP(GetACP());
+
+	// get CPU frequency
+	LARGE_INTEGER freq;
+	if (!QueryPerformanceFrequency(&freq)) {
+		WinAPI_perror("QueryPerformanceFrequency");
+		exit(EXIT_FAILURE);
+	}
+
+	QPF_frequency = freq.QuadPart;
+# endif
+}
+
+long double clock_hr_microsec(void) {
+# if defined(SYS_NT)
+	// FIXME: less accurate than Unix
+
+	LARGE_INTEGER counter;
+	if (!QueryPerformanceCounter(&counter)) {
+		WinAPI_perror("QueryPerformanceCounter");
+		exit(EXIT_FAILURE);
+	}
+	return (long double) (counter.QuadPart * 1000000ULL);
+# elif defined(SYS_UNIX)
+	struct timespec ts;
+	clock_gettime(CLOCK_MONOTONIC_RAW, &ts);
+	return ((long double) (ts.tv_sec * 1000000000ULL + ts.tv_nsec)) / 1000.l;
+# else
+	return (long double) (clock() * 1000000ULL);
+# endif
+}
+
+clock_hr_microsec_t clock_hr_microsec_diff(clock_hr_microsec_t a,
+                                           clock_hr_microsec_t b) {
+	return CLOCK_HR_DIFFTIME_MS(a, b);
+}
+
+# ifdef SYS_NT
+void WinAPI_perror(const char* s) {
+	DWORD errorCode = GetLastError();
+	LPSTR errorString = NULL;
+	FormatMessage(
+		FORMAT_MESSAGE_ALLOCATE_BUFFER |
+		FORMAT_MESSAGE_FROM_SYSTEM |
+		FORMAT_MESSAGE_IGNORE_INSERTS,
+		NULL,
+		errorCode,
+		MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+		(LPSTR)&errorString,
+		0,
+		NULL
+	);
+
+	if (errorString == NULL) {
+		errorString = "???\n";
+		WinAPI_perror_COMMON_MACRO;
+	} else {
+		WinAPI_perror_COMMON_MACRO;
+		LocalFree(errorString);
+	}
+}
+# endif
+
+#ifdef TEST
+# include <stdio.h>
+
+int main(void) {
+	clock_hr_microsec_init();
+
+	clock_hr_microsec_t t1 = 0, t2 = 0;
+
+	t1 = clock_hr_microsec();
+
+	int counter = 0;
+	printf("[");
+	for (int i = 1; i <= 240; i += 3, counter++) {
+		if (i >= 8 && (counter & 7) == 0) {
+			printf("\n ");
+		}
+		printf("0x%02X", i);
+
+		if (i <= 237) {
+			printf(", ");
+		}
+	}
+	puts("]\n");
+
+	t2 = clock_hr_microsec();
+
+	printf("Counter = %d\n"
+	       "Time: %" CLOCK_HR_MICROSEC_PRI " microsec\n",
+	       counter,
+	       clock_hr_microsec_diff(t2, t1));
+}
+#endif

c-programming/benchmarking/clock_hr_microsec.h

@@ -0,0 +1,43 @@
+/*
+ * clock_hr_microsec.h
+ *
+ * Author: Intel A80486DX2-66
+ * License: Unlicense
+ */
+
+#ifndef _CLOCK_HR_MICROSEC_H
+#define _CLOCK_HR_MICROSEC_H
+
+#include <stdio.h>
+
+// typedefs
+typedef long double clock_hr_microsec_t;
+
+// print specifiers
+#define CLOCK_HR_MICROSEC_PRI ".3Lf"
+
+// system identification
+#ifdef _WIN32
+# define SYS_NT
+# include <windows.h>
+#endif
+
+#if defined(__unix__) || defined(__APPLE__)
+# define SYS_UNIX
+#endif
+
+// macros
+#if defined(SYS_UNIX) && !defined(CLOCK_MONOTONIC_RAW)
+# define CLOCK_MONOTONIC_RAW CLOCK_MONOTONIC
+#endif
+
+// function prototypes
+void clock_hr_microsec_init(void);
+clock_hr_microsec_t clock_hr_microsec(void);
+clock_hr_microsec_t clock_hr_microsec_diff(clock_hr_microsec_t a,
+                                           clock_hr_microsec_t b);
+#ifdef SYS_NT
+void WinAPI_perror(const char* s);
+#endif
+
+#endif /* _CLOCK_HR_MICROSEC_H */