/*
**  Helper routines for the innfeed program.
**
**  Written by James Brister <brister@vix.com>
*/

#include "portable/system.h"

#include "innfeed.h"

#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
#include <netdb.h>
#include <netinet/in.h>
#include <signal.h>
#include <sys/param.h>
#include <sys/stat.h>
#include <syslog.h>
#include <time.h>

/* FIXME: Default to a max length of 256 characters for path names if the
   host headers doesn't give better information.  Should be replaced by the
   code from Stevens. */
#ifndef PATH_MAX
#    define PATH_MAX 256
#endif

#include "inn/libinn.h"
#include "inn/messages.h"

#include "endpoint.h"
#include "misc.h"
#include "tape.h"

unsigned int openfds;
unsigned int loggingLevel;
char **PointersFreedOnExit;
char *timeToStringFormat = 0;


/* Log a message to stderr, called from warn or die.  Mostly the same as the
   standard message_log_stderr, but prepends the date to each line. */
void
error_log_stderr_date(int len UNUSED, const char *fmt, va_list args, int err)
{
    char timebuff[30];
    time_t now;
    struct tm *tm;

    now = time(NULL);
    tm = localtime(&now);
    strftime(timebuff, sizeof(timebuff), "%Y-%m-%d %H:%M:%S", tm);
    fprintf(stderr, "%s %s: ", timebuff,
            (message_program_name ? message_program_name : "UNKNOWN"));
    vfprintf(stderr, fmt, args);
    if (err)
        fprintf(stderr, ": %s", strerror(err));
    fprintf(stderr, "\n");
}

/* An alternate version of die, used when we don't want to dump core.  This
   should somehow eventually be phased out to simplify things; it's
   basically a copy of die() from lib/error.c that ignores the cleanup
   handler and has innfeed's handlers hard-coded (ugh). */
void
logAndExit(int status, const char *format, ...)
{
    va_list args;
    int length;

    va_start(args, format);
    length = vsnprintf(NULL, 0, format, args);
    va_end(args);
    va_start(args, format);
    error_log_stderr_date(length, format, args, 0);
    va_end(args);
    va_start(args, format);
    message_log_syslog_err(length, format, args, 0);
    va_end(args);
    exit(status);
}


void
d_printf(unsigned int level, const char *fmt, ...)
{
    static pid_t myPid;
    char timeString[30];
    time_t now;
    struct tm *tm;
    va_list ap;

    if (myPid == 0)
        myPid = getpid();

    if (loggingLevel < level)
        return;

    now = theTime();
    tm = localtime(&now);
    strftime(timeString, sizeof(timeString), "%b %d %H:%M:%S", tm);

    va_start(ap, fmt);
    fprintf(stderr, "%s %s[%ld]: ", timeString,
            (message_program_name ? message_program_name : "UNKNOWN"),
            (long) myPid);
    vfprintf(stderr, fmt, ap);
    va_end(ap);
}

void
logOrPrint(int level, FILE *fp, const char *fmt, ...)
{
    va_list ap;

    va_start(ap, fmt);
    if (fp != NULL) {
        vfprintf(fp, fmt, ap);
        fputc('\n', fp);
    } else {
        char buffer[512]; /* gag me */

        vsnprintf(buffer, sizeof(buffer), fmt, ap);
        syslog(level, "%s", buffer);
    }
    va_end(ap);
}


/* return true if the file exists and is a regular file. */
bool
fileExistsP(const char *filename)
{
    struct stat buf;

    if (stat(filename, &buf) < 0)
        return false;

    return (S_ISREG(buf.st_mode) ? true : false);
}


bool
isDirectory(const char *filename)
{
    struct stat buf;

    if (stat(filename, &buf) < 0)
        return false;

    return (S_ISDIR(buf.st_mode) ? true : false);
}


bool
getNntpResponse(char *p, int *code, char **rest)
{
    bool rval = true;
    int cd = 0;
    int digits = 0;

    if (rest)
        *rest = 0;
    *code = 0;

    if (p == NULL)
        return false;

    while (*p && isspace((unsigned char) *p))
        p++;

    while (*p && isdigit((unsigned char) *p)) {
        digits++;
        cd = (cd * 10) + (*p - '0');
        p++;
    }

    if (digits != 3)
        return false;

    if (*p == '-')
        p++;

    while (*p && isspace((unsigned char) *p))
        p++;

    if (rest)
        *rest = p;

    *code = cd;

    return rval;
}


/* Pull out a message id from a response on to a streaming command */
char *
getMsgId(const char *p)
{
    const char *q;
    char *rval;

    while (*p && isspace((unsigned char) *p))
        p++;
    while (*p && !isspace((unsigned char) *p))
        p++; /* skip response code */
    while (*p && isspace((unsigned char) *p))
        p++;

    if (*p == '\0')
        return NULL;

    q = p;
    while (*q && !isspace((unsigned char) *q))
        q++;

    rval = xstrndup(p, q - p);

    return rval;
}


char *
findNonBlankString(char *ptr, char **tail)
{
    char *p, *q;

    for (p = ptr; *p && isspace((unsigned char) *p); p++)
        /* nada */;
    if (!*p)
        return NULL;

    for (q = p; *q && !isspace((unsigned char) *q); q++)
        /* nada */;

    *tail = q;

    return p;
}


/* strtok can't handle zero length tokens. */
char *
mystrtok(char *line, const char *sep)
{
    static char *newPoint;
    char *oldline;

    if (line == NULL && newPoint == NULL)
        return NULL;

    if (line != NULL) {
        oldline = line;
        while (*line != '\0' && strchr(sep, *line) == NULL)
            line++;

        if (*line == '\0')
            newPoint = NULL;
        else {
            newPoint = line + 1;
            *line = '\0';
        }
    } else {
        if (newPoint == NULL)
            return NULL;

        oldline = newPoint;
        line = oldline;

        while (*line != '\0' && strchr(sep, *line) == NULL)
            line++;

        if (*line == '\0')
            newPoint = NULL;
        else {
            newPoint = line + 1;
            *line = '\0';
        }
    }

    return oldline;
}


void
trim_ws(char *string)
{
    char *p;
    unsigned int len;

    assert(string != NULL);

    len = strlen(string);
    if (len == 0)
        return;

    for (p = string + len - 1; p >= string && isspace((unsigned char) *p); p--)
        /* nada */;
    *++p = '\0';
}


/* Not using plain flock or lockf 'cause I don't want to waste file
   descriptors. This routine is based on the file shlock.c from INN. */
bool
lockFile(const char *fileName)
{
    char buff[20];
    char tmpName[PATH_MAX + sizeof(long) + 10], realName[PATH_MAX];
    char *p;
    int fd, i;
    pid_t pid = getpid();

    strlcpy(realName, fileName, sizeof(realName));
    if ((p = strrchr(realName, '/')) != NULL) {
        *p = '\0';
        snprintf(tmpName, sizeof(tmpName), "%s/lockf%ld", realName,
                 (long) pid);
        *p = '/';
    } else
        snprintf(tmpName, sizeof(tmpName), "lockf%ld", (long) pid);

    /* Create the temporary name for the lock file. */
    while ((fd = open(tmpName, O_RDWR | O_CREAT | O_EXCL, 0644)) < 0) {
        switch (errno) {
        default:
            unlink(tmpName);
            syswarn("ME lock file open: %s", tmpName);
            return false;

        case EEXIST:
            if (unlink(tmpName) < 0) {
                syswarn("ME lock file unlink: %s", tmpName);
                return false;
            }
            break;
        }
    }

    /* stick our pid in the temp file. */
    snprintf(buff, sizeof(buff), "%ld\n", (long) pid);
    if (write(fd, buff, (size_t) strlen(buff)) != (int) strlen(buff)) {
        syswarn("ME lock file pid-write");
        close(fd);
        unlink(tmpName);
        return false;
    }
    close(fd);

    /* now link the real name to the temp file. */
    while (link(tmpName, realName) < 0) {
        switch (errno) {
        default: /* opps. bailing out. */
            syswarn("ME lock file link: %s", realName);
            unlink(tmpName);
            return false;

        case EEXIST:
            /* the real lock file exists. So pull out the pid in there and
               see if that process is still alive. */
            if ((fd = open(realName, O_RDONLY)) < 0) {
                syswarn("ME lock file open: %s", realName);
                unlink(tmpName);
                return false;
            }

            if ((i = read(fd, buff, sizeof(buff) - 1)) <= 0) {
                close(fd);
                unlink(tmpName);
                return false;
            }
            close(fd);

            buff[i] = '\0';
            pid = (pid_t) atol(buff);
            if (pid <= 0) {
                warn("ME lock bad-pid info in %s: %s", realName, buff);
                unlink(tmpName);
                return false;
            }

            /* now send a null signal to the process named inside to see if
               it's still alive. */
            if (kill(pid, 0) == 0) {
                warn("ME lock in-use already: %s by pid %ld", realName,
                     (unsigned long) pid);
                unlink(tmpName);
                return false; /* process is still alive */
            }

            /* process that took out the lock is gone */
            if (unlink(realName) < 0) {
                syswarn("ME lock file unlink: %s", realName);
                unlink(tmpName);
                return false;
            }
        }
    }

    unlink(tmpName);

    return true;
}


void
unlockFile(const char *lockfile)
{
    unlink(lockfile);
}


bool
endsIn(const char *string, const char *tail)
{
    size_t len = strlen(tail);
    size_t slen = strlen(string);

    if (slen < len)
        return false;
    else if (strcmp(string + slen - len, tail) == 0)
        return true;
    else
        return false;
}


/* append the contents of src to dest. src is removed if append if
   successful */
bool
appendFile(const char *dest, const char *src)
{
    FILE *inTmp, *outTmp;
    char buff[BUFSIZ];
    size_t rval;

    /* append the outputFilename file to the inputFilename file */
    if ((outTmp = fopen(dest, "a")) == NULL)
        die("fopen (%s): %s", dest, strerror(errno));
    if ((inTmp = fopen(src, "r")) == NULL)
        die("fopen (%s): %s", src, strerror(errno));

    while ((rval = fread(buff, sizeof(char), BUFSIZ, inTmp)) > 0) {
        if (fwrite(buff, sizeof(char), rval, outTmp) != rval)
            die("fwrite: %s", strerror(errno));
    }

    if (ferror(inTmp))
        die("Error on inTmp in newTape");
    if (ferror(outTmp))
        die("Error on outTmp in newTape");

    if (fclose(inTmp) != 0)
        die("fclose (inTmp): appendFile (%s,%s): %s", dest, src,
            strerror(errno));

    if (fclose(outTmp) != 0)
        die("fclose (outTmp): appendFile (%s,%s): %s", dest, src,
            strerror(errno));

    if (unlink(src) != 0)
        die("unlink (%s): %s", src, strerror(errno));

    return true;
}


/* return true if file1 is older than file2 */
bool
isOlder(const char *file1, const char *file2)
{
    struct stat buf1;
    struct stat buf2;

    if (stat(file1, &buf1) < 0)
        return false;

    if (stat(file2, &buf2) < 0)
        return false;

    return ((buf1.st_mtime < buf2.st_mtime) ? true : false);
}


void
freeCharP(char *charp)
{
    free(charp);
}


/* return the length of the file reference by the given file descriptor */
long
fileLength(int fd)
{
    struct stat buf;

    if (fstat(fd, &buf) < 0)
        return false;

    return ((long) buf.st_size);
}


const char *
boolToString(bool val)
{
    return val ? "true" : "false";
}

char *
timeToString(time_t t, char *buffer, size_t size)
{
    static const char defaultFormat[] = "%a %b %d %H:%M:%S %Y";
    const struct tm *const tm = localtime(&t);
#if __GNUC__ > 4
#    pragma GCC diagnostic ignored "-Wformat-nonliteral"
#endif
    strftime(buffer, size,
             timeToStringFormat == 0 ? defaultFormat : timeToStringFormat, tm);
#if __GNUC__ > 4
#    pragma GCC diagnostic warning "-Wformat-nonliteral"
#endif
    return buffer;
}

void
addPointerFreedOnExit(char *pointerToFree)
{
    static int totalPointers = 0;
    static int nextPointer = 0;

    if (nextPointer == 0 || nextPointer == totalPointers - 1) {
        int i;

        totalPointers += 16;
        if (PointersFreedOnExit == NULL)
            PointersFreedOnExit = xmalloc(sizeof(char *) * totalPointers);
        else
            PointersFreedOnExit =
                xrealloc(PointersFreedOnExit, sizeof(char *) * totalPointers);

        for (i = nextPointer; i < totalPointers; i++)
            PointersFreedOnExit[i] = NULL;
    }
    PointersFreedOnExit[nextPointer++] = pointerToFree;
}


/* borrows heavily from the shrinkfile program by chongo. */
bool
shrinkfile(FILE *fp, long size, char *name, const char *mode)
{
    long currlen = ftello(fp);
    char *tmpname;
    char buffer[BUFSIZ];
    FILE *tmpFp;
    int c;
    int i;
    int fd;

    if (currlen <= size) {
        d_printf(1, "No need to shrink file (%s %ld vs %ld\n", name, size,
                 currlen);
        return true;
    }

    /* create a temp file. */
    tmpname = concat(name, ".XXXXXX", (char *) 0);
    fd = mkstemp(tmpname);

    if (fd < 0) {
        syswarn("ME error creating temp shrink file for %s", name);
        free(tmpname);
        return false;
    }

    if ((tmpFp = fdopen(fd, "w")) == NULL) {
        syswarn("ME error opening temp shrink file %s", tmpname);
        free(tmpname);
        return false;
    }

    if (fseeko(fp, currlen - size, SEEK_SET) != 0) {
        fclose(tmpFp);
        warn("ME error seeking to point %ld in %s", currlen - size, name);
        free(tmpname);
        return false;
    }

    /* find the end of the next line in the shrinking file. */
    while ((c = fgetc(fp)) != '\n')
        if (c == EOF) {
            warn("ME no newline in shrinking file %s", name);
            fclose(tmpFp);
            fseeko(fp, currlen, SEEK_SET);
            free(tmpname);
            return false;
        }

    /* copy the tail of the shrinking file to the temp file. */
    while ((i = fread(buffer, 1, sizeof(buffer), fp)) > 0) {
        if (fwrite(buffer, 1, i, tmpFp) != (size_t) i) {
            fclose(tmpFp);
            syswarn("ME fwrite failed to temp shrink file %s", tmpname);
            fseeko(fp, currlen, SEEK_SET);
            free(tmpname);
            return false;
        }
    }

    if (i < 0)
        logAndExit(1, "ME fread failed on file %s: %s", name, strerror(errno));

    fclose(tmpFp);

    if (unlink(name) != 0)
        logAndExit(1, "ME oserr unlink %s: %s", name, strerror(errno));

    /* we're in the same directory so this is ok. */
    if (rename(tmpname, name) != 0)
        logAndExit(1, "ME oserr rename %s, %s: %s", tmpname, name,
                   strerror(errno));

    if (freopen(name, mode, fp) != fp)
        logAndExit(1, "ME freopen on shrink file failed %s: %s", name,
                   strerror(errno));

    fseeko(fp, 0, SEEK_END);
    size = ftello(fp);

    notice("ME file %s shrunk from %ld to %ld", name, currlen, size);

    free(tmpname);

    return true;
}


long
pathMax(const char *pathname UNUSED)
{
    static long rval = 0;

    if (rval > 0)
        return rval;

#if defined(PATH_MAX)

    rval = PATH_MAX;

#elif defined(_POSIX_PATH_MAX)

    rval = _POSIX_PATH_MAX;

#elif defined(DO_HAVE_PATHCONF) && defined(_PC_PATH_MAX)

    if (pathname == NULL)
        pathname = "/tmp";

    rval = pathconf(pathname, _PC_PATH_MAX);

#else

    rval = 255;
    if (!logged) {
        syslog(LOG_ERR, NO_PATH_MAX, rval);
        logged = true;
    }

#endif

    return rval;
}
