Initial commit

README.md

+custos
+======
+
+Quis custodiet?
+
+Build
+-----
+
+```console
+$ premake5 gmake2
+$ make
+```

premake5.lua

+workspace "custos"
+    configurations { "debug", "release" }
+    kind "ConsoleApp"
+    language "C"
+    cdialect "C11"
+    defines { "_POSIX_C_SOURCE=200112L" }
+    warnings "Extra"
+
+    filter "configurations:debug"
+        defines { "DEBUG" }
+        symbols "On"
+
+    filter "configurations:release"
+        defines { "NDEBUG" }
+        optimize "On"
+
+    filter "toolset:clang or gcc"
+        enablewarnings { "pedantic", "conversion" }
+
+    filter { "toolset:clang or gcc", "tags:test" }
+        buildoptions { "-fsanitize=address,undefined", "-fstack-protector" }
+        linkoptions { "-fsanitize=address,undefined", "-fstack-protector" }
+
+    include "src"

src/main.c

+#include <errno.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <signal.h>
+#include <time.h>
+
+#include "test.h"
+#include "utils.h"
+
+#define DATE_FMT "%Y-%m-%dT%H:%M:%S"
+#define DATE_SIZE sizeof("YYYY-MM-DDTHH:MM:SS")
+
+struct config {
+    struct timespec t;
+};
+
+struct module {
+    const char *name;
+    void *data;
+    void *(*init)(void);
+    bool (*destroy)(void*);
+    bool (*update)(void*);
+};
+
+static sig_atomic_t interrupted = 0;
+
+static struct module modules[] = {{
+    .name = "test",
+    .init = test_init,
+    .destroy = test_destroy,
+    .update = test_update,
+}};
+
+static void sigint_handler(int s) {
+    (void)s;
+    interrupted = 1;
+}
+
+static bool print_header(void) {
+    time_t t = {0};
+    if(time(&t) == -1)
+        return LOG_ERRNO("time"), false;
+    struct tm tm = {0};
+    if(!localtime_r(&t, &tm))
+        return LOG_ERRNO("localtime_r"), false;
+    char str[DATE_SIZE] = {0};
+    if(strftime(str, sizeof(str), DATE_FMT, &tm) != sizeof(str) - 1)
+        return LOG_ERR("strftime failed\n"), false;
+    printf("\n%s\n\n", str);
+    return true;
+}
+
+static bool sleep(struct config *config) {
+    struct timespec *t = &config->t;
+    ++t->tv_sec;
+    while(clock_nanosleep(CLOCK_MONOTONIC, TIMER_ABSTIME, t, NULL) == -1)
+        if(errno != EINTR)
+            return LOG_ERRNO("clock_nanosleep"), false;
+    return true;
+}
+
+static bool init_config(struct config *c) {
+    struct sigaction sa = {.sa_handler = sigint_handler};
+    sigemptyset(&sa.sa_mask);
+    if(sigaction(SIGINT, &sa, NULL) == -1)
+        return LOG_ERRNO("signaction"), false;
+    if(clock_gettime(CLOCK_MONOTONIC, &c->t) == -1)
+        return LOG_ERRNO("clock_gettime"), false;
+    return true;
+}
+
+static bool init_modules(void) {
+    for(size_t i = 0; i != ARRAY_SIZE(modules); ++i) {
+        struct module *const m = modules + i;
+        if(!(m->data = m->init())) {
+            LOG_ERR("failed to initialize module \"%s\"\n", m->name);
+            return false;
+        }
+    }
+    return true;
+}
+
+static bool destroy_modules(void) {
+    bool ret = true;
+    for(size_t i = 0; i != ARRAY_SIZE(modules); ++i) {
+        struct module *const m = modules + i;
+        if(!m->destroy(m->data)) {
+            LOG_ERR("failed to destroy module \"%s\"\n", m->name);
+            ret = false;
+        }
+    }
+    return ret;
+}
+
+static bool update_modules(void) {
+    for(size_t i = 0; i != ARRAY_SIZE(modules); ++i) {
+        struct module *const m = modules + i;
+        if(!m->update(m->data)) {
+            LOG_ERR("failed to update module \"%s\"\n", m->name);
+            return false;
+        }
+    }
+    return true;
+}
+
+int main(void) {
+    struct config config = {0};
+    if(!(init_config(&config) && init_modules()))
+        return 1;
+    while(!interrupted)
+        if(!(print_header() && update_modules() && sleep(&config)))
+            goto err;
+    return !destroy_modules();
+err:
+    destroy_modules();
+    return 1;
+}

src/premake5.lua

+project "custos"
+    files {
+        "main.c",
+        "test.h",
+        "test.c",
+        "utils.c",
+        "utils.h",
+    }
+
+    configuration "debug"

src/test.c

+#include "test.h"
+
+#include <errno.h>
+#include <stdio.h>
+
+void *test_init(void) {
+    puts(__func__);
+    return &errno;
+}
+
+bool test_destroy(void *d) {
+    (void)d;
+    puts(__func__);
+    return true;
+}
+
+bool test_update(void *d) {
+    (void)d;
+    puts(__func__);
+    return true;
+}

src/test.h

+#ifndef CUSTOS_TEST_H
+#define CUSTOS_TEST_H
+
+#include <stdbool.h>
+
+void *test_init(void);
+bool test_destroy(void *d);
+bool test_update(void *d);
+
+#endif

src/utils.c

+#include "utils.h"

src/utils.h

+#ifndef CUSTOS_UTILS_H
+#define CUSTOS_UTILS_H
+
+#include <errno.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdio.h>
+#include <string.h>
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof(*x))
+#define LOG_ERR(...) log_err(__func__, __LINE__, __VA_ARGS__)
+#define LOG_ERRNO(...) log_errno(__func__, __LINE__, __VA_ARGS__)
+
+static inline void log_err(
+    const char *restrict fn, int line, const char *restrict fmt, ...);
+static inline void log_errno(
+    const char *restrict fn, int line, const char *restrict fmt, ...);
+static inline void vlog_err(
+    const char *restrict fn, int line, const char *restrict fmt, va_list args);
+static inline void vlog_errno(
+    const char *restrict fn, int line, const char *restrict fmt, va_list args);
+
+inline void log_err(
+    const char *restrict fn, int line, const char *restrict fmt, ...)
+{
+    va_list args;
+    va_start(args, fmt);
+    vlog_err(fn, line, fmt, args);
+    va_end(args);
+}
+
+inline void log_errno(
+    const char *restrict fn, int line, const char *restrict fmt, ...)
+{
+    va_list args;
+    va_start(args, fmt);
+    vlog_errno(fn, line, fmt, args);
+    va_end(args);
+}
+
+inline void vlog_err(
+    const char *restrict fn, int line, const char *restrict fmt, va_list args)
+{
+    fprintf(stderr, "%s:%d: ", fn, line);
+    vfprintf(stderr, fmt, args);
+}
+
+inline void vlog_errno(
+    const char *restrict fn, int line, const char *restrict fmt, va_list args)
+{
+    vlog_err(fn, line, fmt, args);
+    fprintf(stderr, ": %s\n", strerror(errno));
+}
+
+#endif