#include <stdio.h>
#include "gcc-compat.h"
- #include "error.h"
+ #include "err.h"
#include "log.h"
- #include "string.h"
+ #include "str.h"
+#include "daemon.h"
/**
* Do the usual stuff to become a daemon.
--- /dev/null
-__printf_2_3 void dss_log(int ll, const char* fmt,...);
+ /*
+ * Copyright (C) 2006-2010 Andre Noll <maan@systemlinux.org>
+ *
+ * Licensed under the GPL v2. For licencing details see COPYING.
+ */
+ extern char *dss_errlist[];
+ extern char *dss_error_txt;
+
++void dss_log_set_params(int ll, const char *file, int line, const char *func);
++__printf_1_2 void dss_log(const char* fmt,...);
+
+ /**
+ * This bit indicates whether a number is considered a system error number
+ * If yes, the system errno is just the result of clearing this bit from
+ * the given number.
+ */
+ #define SYSTEM_ERROR_BIT 30
+
+ /** Check whether the system error bit is set. */
+ #define IS_SYSTEM_ERROR(num) (!!((num) & (1 << SYSTEM_ERROR_BIT)))
+
+ /** Set the system error bit for the given number. */
+ #define ERRNO_TO_DSS_ERROR(num) ((num) | (1 << SYSTEM_ERROR_BIT))
+
+ /**
+ * dss' version of strerror(3).
+ *
+ * \param num The error number.
+ *
+ * \return The error text of \a num.
+ */
+ static inline char *dss_strerror(int num)
+ {
+ assert(num > 0);
+ if (IS_SYSTEM_ERROR(num))
+ return strerror((num) & ((1 << SYSTEM_ERROR_BIT) - 1));
+ else
+ return dss_errlist[num];
+ }
+
+ #define DSS_ERRORS \
+ DSS_ERROR(SUCCESS, "success"), \
+ DSS_ERROR(SYNTAX, "syntax error"), \
+ DSS_ERROR(ATOI_OVERFLOW, "value too large"), \
+ DSS_ERROR(STRTOLL, "unknown strtoll error"), \
+ DSS_ERROR(ATOI_NO_DIGITS, "no digits found in string"), \
+ DSS_ERROR(ATOI_JUNK_AT_END, "further characters after number"), \
+ DSS_ERROR(INVALID_NUMBER, "invalid number"), \
+ DSS_ERROR(STRFTIME, "strftime() failed"), \
+ DSS_ERROR(LOCALTIME, "localtime() failed"), \
+ DSS_ERROR(NULL_OPEN, "can not open /dev/null"), \
+ DSS_ERROR(DUP_PIPE, "exec error: can not create pipe"), \
+ DSS_ERROR(INVOLUNTARY_EXIT, "unexpected termination cause"), \
+ DSS_ERROR(BAD_EXIT_CODE, "unexpected exit code"), \
+ DSS_ERROR(SIGNAL_SIG_ERR, "signal() returned SIG_ERR"), \
+ DSS_ERROR(SIGNAL, "caught terminating signal"), \
+ DSS_ERROR(BUG, "values of beta might cause dom!"), \
+ DSS_ERROR(NOT_RUNNING, "dss not running")
+
+ /**
+ * This is temporarily defined to expand to its first argument (prefixed by
+ * 'E_') and gets later redefined to expand to the error text only
+ */
+ #define DSS_ERROR(err, msg) E_ ## err
+
+ enum dss_error_codes {
+ DSS_ERRORS
+ };
+ #undef DSS_ERROR
+ #define DSS_ERROR(err, msg) msg
+ #define DEFINE_DSS_ERRLIST char *dss_errlist[] = {DSS_ERRORS}
#include "gcc-compat.h"
#include "log.h"
- #include "error.h"
- #include "string.h"
+ #include "err.h"
+ #include "str.h"
+#include "exec.h"
/**
* Spawn a new process using execvp().
--- /dev/null
-
+ /*
+ * Copyright (C) 2006-2010 Andre Noll <maan@systemlinux.org>
+ *
+ * Licensed under the GPL v2. For licencing details see COPYING.
+ */
+
++#include <stdio.h>
+ #include <unistd.h>
+ #include <assert.h>
+ #include <string.h>
+ #include <errno.h>
+ #include <sys/types.h>
+ #include <dirent.h>
+ #include <sys/stat.h>
+ #include <fcntl.h>
+
+ #include "gcc-compat.h"
+ #include "err.h"
+ #include "str.h"
++#include "file.h"
+
+ /**
+ * Call a function for each subdirectory of the current working directory.
+ *
+ * \param dirname The directory to traverse.
+ * \param func The function to call for each subdirecrtory.
+ * \param private_data Pointer to an arbitrary data structure.
+ *
+ * For each top-level directory under \a dirname, the supplied function \a func is
+ * called. The full path of the subdirectory and the \a private_data pointer
+ * are passed to \a func.
+ *
+ * \return This function returns immediately if \a func returned a negative
+ * value. In this case \a func must set error_txt and this negative value is
+ * returned to the caller. Otherwise the function returns when all
+ * subdirectories have been passed to \a func.
+ */
+
+ int for_each_subdir(int (*func)(const char *, void *), void *private_data)
+ {
+ struct dirent *entry;
+ int ret;
+ DIR *dir = opendir(".");
+
+ if (!dir)
+ return -ERRNO_TO_DSS_ERROR(errno);
+ while ((entry = readdir(dir))) {
+ mode_t m;
+ struct stat s;
+
+ if (!strcmp(entry->d_name, "."))
+ continue;
+ if (!strcmp(entry->d_name, ".."))
+ continue;
+ ret = lstat(entry->d_name, &s) == -1;
+ if (ret == -1) {
+ ret = -ERRNO_TO_DSS_ERROR(errno);
+ goto out;
+ }
+ m = s.st_mode;
+ if (!S_ISDIR(m))
+ continue;
+ ret = func(entry->d_name, private_data);
+ if (ret < 0)
+ goto out;
+ }
+ ret = 1;
+ out:
+ closedir(dir);
+ return ret;
+ }
+ /**
+ * Wrapper for chdir(2).
+ *
+ * \param path The specified directory.
+ *
+ * \return Standard.
+ */
+ int dss_chdir(const char *path)
+ {
+ if (chdir(path) >= 0)
+ return 1;
+ return -ERRNO_TO_DSS_ERROR(errno);
+ }
+
+ /**
+ * Set a file descriptor to non-blocking mode.
+ *
+ * \param fd The file descriptor.
+ *
+ * \return Standard.
+ */
+ __must_check int mark_fd_nonblocking(int fd)
+ {
+ int flags = fcntl(fd, F_GETFL);
+ if (flags < 0)
+ return -ERRNO_TO_DSS_ERROR(errno);
+ flags = fcntl(fd, F_SETFL, ((long)flags) | O_NONBLOCK);
+ if (flags < 0)
+ return -ERRNO_TO_DSS_ERROR(errno);
+ return 1;
+ }
+
+ /**
+ * dss' wrapper for select(2).
+ *
+ * It calls select(2) (with no exceptfds) and starts over if select() was
+ * interrupted by a signal.
+ *
+ * \param n The highest-numbered descriptor in any of the two sets, plus 1.
+ * \param readfds fds that should be checked for readability.
+ * \param writefds fds that should be checked for writablility.
+ * \param timeout_tv upper bound on the amount of time elapsed before select()
+ * returns.
+ *
+ * \return The return value of the underlying select() call on success, the
+ * negative system error code on errors.
+ *
+ * All arguments are passed verbatim to select(2).
+ * \sa select(2) select_tut(2).
+ */
+ int dss_select(int n, fd_set *readfds, fd_set *writefds,
+ struct timeval *timeout_tv)
+ {
+ int ret, err;
+ do {
+ ret = select(n, readfds, writefds, NULL, timeout_tv);
+ err = errno;
+ } while (ret < 0 && err == EINTR);
+ if (ret < 0)
+ return -ERRNO_TO_DSS_ERROR(errno);
+ return ret;
+ }
#include <sys/param.h>
#include "gcc-compat.h"
- #include "string.h"
+ #include "str.h"
#include "log.h"
#include "gcc-compat.h"
- #include "error.h"
+ #include "err.h"
+#include "ipc.h"
#if (defined(__GNUC__) && defined(__i386__))
#define get16bits(d) (*((const uint16_t *) (d)))
--- /dev/null
- DSS_EMERG_LOG("%s\n", dss_strerror(-ret));
+ /*
+ * Copyright (C) 2004-2010 Andre Noll <maan@systemlinux.org>
+ *
+ * Licensed under the GPL v2. For licencing details see COPYING.
+ */
+
+ #include <string.h>
+ #include <errno.h>
+ #include <signal.h>
+ #include <sys/types.h>
+ #include <sys/wait.h>
+ #include <dirent.h>
+ #include <assert.h>
+ #include <stdio.h>
+ #include <unistd.h>
+ #include <signal.h>
+ #include <stdlib.h>
+ #include <sys/select.h>
+
+
+ #include "gcc-compat.h"
+ #include "err.h"
+ #include "log.h"
+ #include "str.h"
+ #include "file.h"
++#include "sig.h"
+
+ static int signal_pipe[2];
+
+ /**
+ * Initialize the signal subsystem.
+ *
+ * This function creates a pipe, the signal pipe, to deliver pending signals to
+ * the application (Bernstein's trick). It should be called during the
+ * application's startup part, followed by subsequent calls to
+ * install_sighandler() for each signal that should be caught.
+ *
+ * signal_init() installs a generic signal handler which is used for all
+ * signals simultaneously. When a signal arrives, this generic signal handler
+ * writes the corresponding signal number to the signal pipe so that the
+ * application can test for pending signals simply by checking the signal pipe
+ * for reading, e.g. by using the select(2) system call.
+ *
+ * \return This function either succeeds or calls exit(2) to terminate
+ * the current process. On success, the file descriptor of the signal pipe is
+ * returned.
+ */
+ int signal_init(void)
+ {
+ int ret;
+ if (pipe(signal_pipe) < 0) {
+ ret = -ERRNO_TO_DSS_ERROR(errno);
+ goto err_out;
+ }
+ ret = mark_fd_nonblocking(signal_pipe[0]);
+ if (ret < 0)
+ goto err_out;
+ ret = mark_fd_nonblocking(signal_pipe[1]);
+ if (ret < 0)
+ goto err_out;
+ return signal_pipe[0];
+ err_out:
- DSS_DEBUG_LOG("child %i exited. Exit status: %i\n", (int)*pid,
- WEXITSTATUS(*status));
++ DSS_EMERG_LOG(("%s\n", dss_strerror(-ret)));
+ exit(EXIT_FAILURE);
+ }
+
+ /*
+ * just write one integer to signal pipe
+ */
+ static void generic_signal_handler(int s)
+ {
+ write(signal_pipe[1], &s, sizeof(int));
+ }
+
+ /**
+ * Reap one child.
+ *
+ * \param pid In case a child died, its pid is returned here.
+ *
+ * Call waitpid() and print a log message containing the pid and the cause of
+ * the child's death.
+ *
+ * \return A (negative) error code on errors, zero, if no child died, one
+ * otherwise. If and only if the function returns one, the content of \a pid is
+ * meaningful.
+ *
+ * \sa waitpid(2)
+ */
+ int reap_child(pid_t *pid, int *status)
+ {
+ *pid = waitpid(-1, status, WNOHANG);
+
+ if (!*pid)
+ return 0;
+ if (*pid < 0)
+ return -ERRNO_TO_DSS_ERROR(errno);
+ if (WIFEXITED(*status))
- DSS_DEBUG_LOG("child %i was killed by signal %i\n", (int)*pid,
- WTERMSIG(*status));
++ DSS_DEBUG_LOG(("child %i exited. Exit status: %i\n", (int)*pid,
++ WEXITSTATUS(*status)));
+ else if (WIFSIGNALED(*status))
- DSS_WARNING_LOG("child %i terminated abormally\n", (int)*pid);
++ DSS_DEBUG_LOG(("child %i was killed by signal %i\n", (int)*pid,
++ WTERMSIG(*status)));
+ else
- DSS_DEBUG_LOG("catching signal %d\n", sig);
++ DSS_WARNING_LOG(("child %i terminated abormally\n", (int)*pid));
+ return 1;
+ }
+
+ /**
+ * Wrapper around signal(2)
+ *
+ * \param sig The number of the signal to catch.
+ *
+ * This installs the generic signal handler for the given signal.
+ *
+ * \return This function returns 1 on success and \p -E_SIGNAL_SIG_ERR on errors.
+ * \sa signal(2)
+ */
+ int install_sighandler(int sig)
+ {
- DSS_DEBUG_LOG("next signal: %d\n", s);
++ DSS_DEBUG_LOG(("catching signal %d\n", sig));
+ if (signal(sig, &generic_signal_handler) != SIG_ERR)
+ return 1;
+ return -E_SIGNAL_SIG_ERR;
+ }
+
+ /**
+ * Return number of next pending signal.
+ *
+ * This should be called if the fd for the signal pipe is ready for reading.
+ *
+ * \return On success, the number of the received signal is returned.
+ * If the read was interrupted by another signal the function returns 0.
+ * Otherwise a negative error code is returned.
+ */
+ int next_signal(void)
+ {
+ int s, err;
+ ssize_t r;
+
+ r = read(signal_pipe[0], &s, sizeof(s));
+ if (r == sizeof(s)) {
- DSS_ERROR_LOG("failed to read from signal pipe\n");
++ DSS_DEBUG_LOG(("next signal: %d\n", s));
+ return s;
+ }
+ err = errno;
+ assert(r < 0);
+ if (err == EAGAIN)
+ return 0;
++ DSS_ERROR_LOG(("failed to read from signal pipe\n"));
+ return -ERRNO_TO_DSS_ERROR(err);
+ }
+
+ /**
+ * Close the signal pipe.
+ */
+ void signal_shutdown(void)
+ {
+ close(signal_pipe[1]);
+ }
--- /dev/null
- DSS_EMERG_LOG("realloc failed (size = %zu), aborting\n",
- size);
+ /*
+ * Copyright (C) 2004-2010 Andre Noll <maan@systemlinux.org>
+ *
+ * Licensed under the GPL v2. For licencing details see COPYING.
+ */
+ #include <string.h>
+ #include <stdlib.h>
+ #include <stdio.h>
+ #include <stdarg.h>
+ #include <assert.h>
+ #include <limits.h>
+ #include <errno.h>
+ #include <pwd.h>
+ #include <sys/types.h>
+ #include <unistd.h>
+
+
+ #include "gcc-compat.h"
+ #include "log.h"
+ #include "err.h"
+ #include "str.h"
+
+ /**
+ * Write a message to a dynamically allocated string.
+ *
+ * \param fmt Usual format string.
+ * \param p Result pointer.
+ *
+ * \sa printf(3). */
+ #define VSPRINTF(fmt, p) \
+ { \
+ int n; \
+ size_t size = 100; \
+ p = dss_malloc(size); \
+ while (1) { \
+ va_list ap; \
+ /* Try to print in the allocated space. */ \
+ va_start(ap, fmt); \
+ n = vsnprintf(p, size, fmt, ap); \
+ va_end(ap); \
+ /* If that worked, return the string. */ \
+ if (n > -1 && n < size) \
+ break; \
+ /* Else try again with more space. */ \
+ if (n > -1) /* glibc 2.1 */ \
+ size = n + 1; /* precisely what is needed */ \
+ else /* glibc 2.0 */ \
+ size *= 2; /* twice the old size */ \
+ p = dss_realloc(p, size); \
+ } \
+ }
+
+ /**
+ * dss' version of realloc().
+ *
+ * \param p Pointer to the memory block, may be \p NULL.
+ * \param size The desired new size.
+ *
+ * A wrapper for realloc(3). It calls \p exit(\p EXIT_FAILURE) on errors,
+ * i.e. there is no need to check the return value in the caller.
+ *
+ * \return A pointer to the newly allocated memory, which is suitably aligned
+ * for any kind of variable and may be different from \a p.
+ *
+ * \sa realloc(3).
+ */
+ __must_check __malloc void *dss_realloc(void *p, size_t size)
+ {
+ /*
+ * No need to check for NULL pointers: If p is NULL, the call
+ * to realloc is equivalent to malloc(size)
+ */
+ assert(size);
+ if (!(p = realloc(p, size))) {
- DSS_EMERG_LOG("malloc failed (size = %zu), aborting\n",
- size);
++ DSS_EMERG_LOG(("realloc failed (size = %zu), aborting\n",
++ size));
+ exit(EXIT_FAILURE);
+ }
+ return p;
+ }
+
+ /**
+ * dss' version of malloc().
+ *
+ * \param size The desired new size.
+ *
+ * A wrapper for malloc(3) which exits on errors.
+ *
+ * \return A pointer to the allocated memory, which is suitably aligned for any
+ * kind of variable.
+ *
+ * \sa malloc(3).
+ */
+ __must_check __malloc void *dss_malloc(size_t size)
+ {
+ void *p;
+ assert(size);
+ p = malloc(size);
+
+ if (!p) {
- DSS_EMERG_LOG("strdup failed, aborting\n");
++ DSS_EMERG_LOG(("malloc failed (size = %zu), aborting\n",
++ size));
+ exit(EXIT_FAILURE);
+ }
+ return p;
+ }
+
+ /**
+ * dss' version of calloc().
+ *
+ * \param size The desired new size.
+ *
+ * A wrapper for calloc(3) which exits on errors.
+ *
+ * \return A pointer to the allocated and zeroed-out memory, which is suitably
+ * aligned for any kind of variable.
+ *
+ * \sa calloc(3)
+ */
+ __must_check __malloc void *dss_calloc(size_t size)
+ {
+ void *ret = dss_malloc(size);
+
+ memset(ret, 0, size);
+ return ret;
+ }
+
+ /**
+ * dss' version of strdup().
+ *
+ * \param s The string to be duplicated.
+ *
+ * A wrapper for strdup(3). It calls \p exit(EXIT_FAILURE) on errors, i.e.
+ * there is no need to check the return value in the caller.
+ *
+ * \return A pointer to the duplicated string. If \p s was the NULL pointer,
+ * an pointer to an empty string is returned.
+ *
+ * \sa strdup(3)
+ */
+
+ __must_check __malloc char *dss_strdup(const char *s)
+ {
+ char *ret;
+
+ if ((ret = strdup(s? s: "")))
+ return ret;
++ DSS_EMERG_LOG(("strdup failed, aborting\n"));
+ exit(EXIT_FAILURE);
+ }
+
+ /**
+ * Allocate a sufficiently large string and print into it.
+ *
+ * \param fmt A usual format string.
+ *
+ * Produce output according to \p fmt. No artificial bound on the length of the
+ * resulting string is imposed.
+ *
+ * \return This function either returns a pointer to a string that must be
+ * freed by the caller or aborts without returning.
+ *
+ * \sa printf(3).
+ */
+ __must_check __printf_1_2 __malloc char *make_message(const char *fmt, ...)
+ {
+ char *msg;
+
+ VSPRINTF(fmt, msg);
+ return msg;
+ }
+
+ /**
+ * Get the home directory of the current user.
+ *
+ * \return A dynammically allocated string that must be freed by the caller. If
+ * the home directory could not be found, this function returns "/tmp".
+ */
+ __must_check __malloc char *get_homedir(void)
+ {
+ struct passwd *pw = getpwuid(getuid());
+ return dss_strdup(pw? pw->pw_dir : "/tmp");
+ }
+
+ /**
+ * Convert a string to a 64-bit signed integer value.
+ *
+ * \param str The string to be converted.
+ * \param value Result pointer.
+ *
+ * \return Standard.
+ *
+ * \sa strtol(3), atoi(3).
+ */
+ int dss_atoi64(const char *str, int64_t *value)
+ {
+ char *endptr;
+ long long tmp;
+
+ errno = 0; /* To distinguish success/failure after call */
+ tmp = strtoll(str, &endptr, 10);
+ if (errno == ERANGE && (tmp == LLONG_MAX || tmp == LLONG_MIN))
+ return -E_ATOI_OVERFLOW;
+ if (errno != 0 && tmp == 0) /* other error */
+ return -E_STRTOLL;
+ if (endptr == str)
+ return -E_ATOI_NO_DIGITS;
+ if (*endptr != '\0') /* Further characters after number */
+ return -E_ATOI_JUNK_AT_END;
+ *value = tmp;
+ return 1;
+ }
+
+ /**
+ * Get the logname of the current user.
+ *
+ * \return A dynammically allocated string that must be freed by the caller. On
+ * errors, the string "unknown user" is returned, i.e. this function never
+ * returns \p NULL.
+ *
+ * \sa getpwuid(3).
+ */
+ __must_check __malloc char *dss_logname(void)
+ {
+ struct passwd *pw = getpwuid(getuid());
+ return dss_strdup(pw? pw->pw_name : "unknown_user");
+ }
+
+ /**
+ * Split string and return pointers to its parts.
+ *
+ * \param args The string to be split.
+ * \param argv_ptr Pointer to the list of substrings.
+ * \param delim Delimiter.
+ *
+ * This function modifies \a args by replacing each occurance of \a delim by
+ * zero. A \p NULL-terminated array of pointers to char* is allocated dynamically
+ * and these pointers are initialized to point to the broken-up substrings
+ * within \a args. A pointer to this array is returned via \a argv_ptr.
+ *
+ * \return The number of substrings found in \a args.
+ */
+ unsigned split_args(char *args, char *** const argv_ptr, const char *delim)
+ {
+ char *p = args;
+ char **argv;
+ size_t n = 0, i, j;
+
+ p = args + strspn(args, delim);
+ for (;;) {
+ i = strcspn(p, delim);
+ if (!i)
+ break;
+ p += i;
+ n++;
+ p += strspn(p, delim);
+ }
+ *argv_ptr = dss_malloc((n + 1) * sizeof(char *));
+ argv = *argv_ptr;
+ i = 0;
+ p = args + strspn(args, delim);
+ while (p) {
+ argv[i] = p;
+ j = strcspn(p, delim);
+ if (!j)
+ break;
+ p += strcspn(p, delim);
+ if (*p) {
+ *p = '\0';
+ p++;
+ p += strspn(p, delim);
+ }
+ i++;
+ }
+ argv[n] = NULL;
+ return n;
+ }
--- /dev/null
- DSS_DEBUG_LOG("now: %jd\n", (intmax_t)now);
+ /*
+ * Copyright (C) 2005-2010 Andre Noll <maan@systemlinux.org>
+ *
+ * Licensed under the GPL v2. For licencing details see COPYING.
+ */
+
+ #include <sys/time.h>
+ #include <time.h>
+ #include <inttypes.h>
+ #include <assert.h>
+ #include <string.h>
+
+ #include "gcc-compat.h"
+ #include "err.h"
+ #include "str.h"
+ #include "log.h"
++#include "time.h"
+
+ /**
+ * Convert struct timeval to milliseconds.
+ *
+ * \param tv The time value value to convert.
+ *
+ * \return The number off milliseconds in \a tv.
+ */
+ long unsigned tv2ms(const struct timeval *tv)
+ {
+ return tv->tv_sec * 1000 + (tv->tv_usec + 500)/ 1000;
+ }
+
+ /**
+ * Convert milliseconds to a struct timeval.
+ *
+ * \param n The number of milliseconds.
+ * \param tv Result pointer.
+ */
+ void ms2tv(long unsigned n, struct timeval *tv)
+ {
+ tv->tv_sec = n / 1000;
+ tv->tv_usec = (n % 1000) * 1000;
+ }
+
+ /**
+ * Convert a double to a struct timeval.
+ *
+ * \param x The value to convert.
+ * \param tv Result pointer.
+ */
+ void d2tv(double x, struct timeval *tv)
+ {
+ tv->tv_sec = x;
+ tv->tv_usec = (x - (double)tv->tv_sec) * 1000.0 * 1000.0 + 0.5;
+ }
+
+ /**
+ * Compute the difference of two time values.
+ *
+ * \param b Minuend.
+ * \param a Subtrahend.
+ * \param diff Result pointer.
+ *
+ * If \a diff is not \p NULL, it contains the absolute value |\a b - \a a| on
+ * return.
+ *
+ * \return If \a b < \a a, this function returns -1, otherwise it returns 1.
+ */
+ int tv_diff(const struct timeval *b, const struct timeval *a, struct timeval *diff)
+ {
+ int ret = 1;
+
+ if ((b->tv_sec < a->tv_sec) ||
+ ((b->tv_sec == a->tv_sec) && (b->tv_usec < a->tv_usec))) {
+ const struct timeval *tmp = a;
+ a = b;
+ b = tmp;
+ ret = -1;
+ }
+ if (!diff)
+ return ret;
+ diff->tv_sec = b->tv_sec - a->tv_sec;
+ if (b->tv_usec < a->tv_usec) {
+ diff->tv_sec--;
+ diff->tv_usec = 1000 * 1000 - a->tv_usec + b->tv_usec;
+ } else
+ diff->tv_usec = b->tv_usec - a->tv_usec;
+ return ret;
+ }
+
+ /**
+ * Add two time values.
+ *
+ * \param a First addend.
+ * \param b Second addend.
+ * \param sum Contains the sum \a + \a b on return.
+ */
+ void tv_add(const struct timeval *a, const struct timeval *b,
+ struct timeval *sum)
+ {
+ sum->tv_sec = a->tv_sec + b->tv_sec;
+ if (a->tv_usec + b->tv_usec >= 1000 * 1000) {
+ sum->tv_sec++;
+ sum->tv_usec = a->tv_usec + b->tv_usec - 1000 * 1000;
+ } else
+ sum->tv_usec = a->tv_usec + b->tv_usec;
+ }
+
+ /**
+ * Compute integer multiple of given struct timeval.
+ *
+ * \param mult The integer value to multiply with.
+ * \param tv The timevalue to multiply.
+ *
+ * \param result Contains \a mult * \a tv on return.
+ */
+ void tv_scale(const unsigned long mult, const struct timeval *tv,
+ struct timeval *result)
+ {
+ result->tv_sec = mult * tv->tv_sec;
+ result->tv_sec += tv->tv_usec * mult / 1000 / 1000;
+ result->tv_usec = tv->tv_usec * mult % (1000 * 1000);
+ }
+
+ /**
+ * Compute a fraction of given struct timeval.
+ *
+ * \param divisor The integer value to divide by.
+ * \param tv The timevalue to divide.
+ * \param result Contains (1 / mult) * tv on return.
+ */
+ void tv_divide(const unsigned long divisor, const struct timeval *tv,
+ struct timeval *result)
+ {
+ uint64_t x = ((uint64_t)tv->tv_sec * 1000 * 1000 + tv->tv_usec) / divisor;
+
+ result->tv_sec = x / 1000 / 1000;
+ result->tv_usec = x % (1000 * 1000);
+ }
+
+ int64_t get_current_time(void)
+ {
+ time_t now;
+ time(&now);
++ DSS_DEBUG_LOG(("now: %jd\n", (intmax_t)now));
+ return (int64_t)now;
+ }