diff options
Diffstat (limited to 'downtimedb.c')
| -rw-r--r-- | downtimedb.c | 191 |
1 files changed, 191 insertions, 0 deletions
diff --git a/downtimedb.c b/downtimedb.c new file mode 100644 index 0000000..007f5be --- /dev/null +++ b/downtimedb.c @@ -0,0 +1,191 @@ +/*- + * Copyright (c) 2009-2013 EPIPE Communications. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + * + * The views and conclusions contained in the software and documentation are + * those of the authors and should not be interpreted as representing official + * policies, either expressed or implied, of EPIPE Communications. + * + * + * Software web site: + * http://dist.epipe.com/downtimed/ + * + * Author contact information: + * opensource@epipe.com + */ + +/* Include config.h in case we use autoconf. */ + +#ifdef HAVE_CONFIG_H +#include "config.h" +#endif + +#include <sys/types.h> + +#include <errno.h> +#include <inttypes.h> + +#ifdef HAVE_PATHS_H +#include <paths.h> +#endif + +#include <stdio.h> +#include <time.h> +#include <unistd.h> + +#include "downtimedb.h" + +/* + * Swap bytes of uint64_t. + * + * We used to be trying to use htobe64() and be64toh(). + * Or htobe64() and betoh64(). + * Or OSSwapHostToBigInt64() and OSSwapBigToHostInt64(). + * + * But the reality is that due to lack of standardization this became + * just a big mess as there is no portable function to do this. Some + * systems (for example RHEL/CentOS 5.5) lack the corresponding functions + * altogether. + * + * Therefore we ignore whatever is available and just define our own + * MY_BSWAP64() macro which is used on little endian architectures. + * + * The implementation is stolen from crypt-sha512.c released into the + * Public Domain by Ulrich Drepper <drepper@redhat.com>. + */ + +#ifndef WORDS_BIGENDIAN +#define MY_BSWAP64(n) \ + (((n) << 56) \ + | (((n) & 0xff00) << 40) \ + | (((n) & 0xff0000) << 24) \ + | (((n) & 0xff000000) << 8) \ + | (((n) >> 8) & 0xff000000) \ + | (((n) >> 24) & 0xff0000) \ + | (((n) >> 40) & 0xff00) \ + | ((n) >> 56)) +#endif + +/* + * Functions for reading from and writing to the downtime database. + */ + +int +downtimedb_read(int fd, struct downtimedb *buf) +{ + int ret; + + errno = 0; + if ((ret = read(fd, (void *)buf, sizeof(struct downtimedb))) + < sizeof(struct downtimedb)) { + if (ret == 0) + return (0); /* eof */ + else { + if (ret != -1) { + /* set errno when it is not a read error */ + errno = EILSEQ; + } + return (-1); /* some sort of error */ + } + } + +#ifndef WORDS_BIGENDIAN + buf->when = (int64_t) MY_BSWAP64((uint64_t) buf->when); +#endif + + return (1); /* 1 record read */ +} + +/* The write function modifies the buffer on the fly to match + * the endianness required in the database. Thus, the supplied + * struct downtimedb will be invalid after calling this function. + */ + +int +downtimedb_write(int fd, struct downtimedb *buf) +{ +#ifndef WORDS_BIGENDIAN + buf->when = (int64_t) MY_BSWAP64((uint64_t) buf->when); +#endif + + errno = 0; + if (write(fd, (void *)buf, sizeof(struct downtimedb)) + < sizeof(struct downtimedb)) + return (-1); + + return (0); +} + +/* + * Return time string of absolute time in static buffer. + * Certainly not thread-safe. + */ + +char * +timestr_abs(time_t t, const char *fmt, int utc) +{ + static char str[256]; + struct tm *lt; + + if (t != 0) { + if ((lt = (utc ? gmtime(&t) : localtime(&t))) == NULL) + goto err; + if (strftime(str, sizeof(str), fmt, lt) == 0) + goto err; + + return (str); + } +err: + /* we have the backslashes here to avoid interpretation as trigraphs */ + return ("?\?\?\?-?\?-?\? ?\?:?\?:?\?"); +} + +/* + * Stolen from top.c. Return time interval in human-readable (?) static + * string. Definitely not thread-safe. + */ + +char * +timestr_int(time_t t) +{ + int days, hrs, mins, secs; + static char str[100]; + + days = t / 86400; + t %= 86400; + hrs = t / 3600; + t %= 3600; + mins = t / 60; + secs = t % 60; + + if (days > 0) + snprintf(str, sizeof(str), "%d+%02d:%02d:%02d", + days, hrs, mins, secs); + else + snprintf(str, sizeof(str), "%02d:%02d:%02d", + hrs, mins, secs); + + return (str); +} + +/* eof */ |