path: root/lib/Plugins/CCpp.cpp

/*
    CCpp.cpp

    Copyright (C) 2009  Zdenek Prikryl (zprikryl@redhat.com)
    Copyright (C) 2009  RedHat inc.

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License along
    with this program; if not, write to the Free Software Foundation, Inc.,
    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#include <set>
#include <iomanip>
//#include <nss.h>
//#include <sechash.h>
#include "abrtlib.h"
#include "strbuf.h"
#include "CCpp.h"
#include "ABRTException.h"
#include "DebugDump.h"
#include "CommLayerInner.h"
#include "Polkit.h"
#include "backtrace.h"
#include "CCpp_sha1.h"

using namespace std;

#define CORE_PATTERN_IFACE      "/proc/sys/kernel/core_pattern"
#define CORE_PATTERN            "|"CCPP_HOOK_PATH" "DEBUG_DUMPS_DIR" %p %s %u %c"
#define CORE_PIPE_LIMIT_IFACE   "/proc/sys/kernel/core_pipe_limit"
/* core_pipe_limit specifies how many dump_helpers might run at the same time
0 - means unlimited, but the it's not guaranteed that /proc/<pid> of crashing
process might not be available for dump_helper
4 - means that 4 dump_helpers can run at the same time, which should be enough
for ABRT, we can miss some crashes, but what are the odds that more processes
crash at the same time? This value has been recommended by nhorman
*/
#define CORE_PIPE_LIMIT "4"

#define DEBUGINFO_CACHE_DIR     LOCALSTATEDIR"/cache/abrt-di"

CAnalyzerCCpp::CAnalyzerCCpp() :
    m_bBacktrace(true),
    m_bMemoryMap(false),
    m_bInstallDebugInfo(true),
    m_nDebugInfoCacheMB(4000)
{}

static string create_hash(const char *pInput)
{
    unsigned int len;

#if 0
{
    char hash_str[SHA1_LENGTH*2 + 1];
    unsigned char hash[SHA1_LENGTH];
    HASHContext *hc;
    hc = HASH_Create(HASH_AlgSHA1);
    if (!hc)
    {
        error_msg_and_die("HASH_Create(HASH_AlgSHA1) failed"); /* paranoia */
    }
    HASH_Begin(hc);
    HASH_Update(hc, (const unsigned char*)pInput, strlen(pInput));
    HASH_End(hc, hash, &len, sizeof(hash));
    HASH_Destroy(hc);

    char *d = hash_str;
    unsigned char *s = hash;
    while (len)
    {
        *d++ = "0123456789abcdef"[*s >> 4];
        *d++ = "0123456789abcdef"[*s & 0xf];
        s++;
        len--;
    }
    *d = '\0';
//log("hash1:%s str:'%s'", hash_str, pInput);
}
#endif

    char hash_str[SHA1_RESULT_LEN*2 + 1];
    unsigned char hash2[SHA1_RESULT_LEN];
    sha1_ctx_t sha1ctx;
    sha1_begin(&sha1ctx);
    sha1_hash(pInput, strlen(pInput), &sha1ctx);
    sha1_end(hash2, &sha1ctx);
    len = SHA1_RESULT_LEN;

    char *d = hash_str;
    unsigned char *s = hash2;
    while (len)
    {
        *d++ = "0123456789abcdef"[*s >> 4];
        *d++ = "0123456789abcdef"[*s & 0xf];
        s++;
        len--;
    }
    *d = '\0';
//log("hash2:%s str:'%s'", hash_str, pInput);

    return hash_str;
}

/* Returns status. See `man 2 wait` for status information. */
static int ExecVP(char **pArgs, uid_t uid, int redirect_stderr, string& pOutput)
{
    /* Nuke everything which may make setlocale() switch to non-POSIX locale:
     * we need to avoid having gdb output in some obscure language.
     */
    static const char *const unsetenv_vec[] = {
        "LANG",
        "LC_ALL",
        "LC_COLLATE",
        "LC_CTYPE",
        "LC_MESSAGES",
        "LC_MONETARY",
        "LC_NUMERIC",
        "LC_TIME",
        NULL
    };

    int flags = EXECFLG_INPUT_NUL | EXECFLG_OUTPUT | EXECFLG_SETGUID | EXECFLG_SETSID | EXECFLG_QUIET;
    if (redirect_stderr)
        flags |= EXECFLG_ERR2OUT;
    VERB1 flags &= ~EXECFLG_QUIET;

    int pipeout[2];
    pid_t child = fork_execv_on_steroids(flags, pArgs, pipeout, (char**)unsetenv_vec, /*dir:*/ NULL, uid);

    int r;
    char buff[1024];
    while ((r = read(pipeout[0], buff, sizeof(buff) - 1)) > 0)
    {
        buff[r] = '\0';
        pOutput += buff;
    }
    close(pipeout[0]);

    int status;
    waitpid(child, &status, 0); /* prevent having zombie child process */

    return status;
}

static void GetBacktrace(const char *pDebugDumpDir,
                         const char *pDebugInfoDirs,
                         string& pBacktrace)
{
    update_client(_("Generating backtrace"));

    string UID;
    string executable;
    {
        CDebugDump dd;
        dd.Open(pDebugDumpDir);
        dd.LoadText(FILENAME_EXECUTABLE, executable);
        dd.LoadText(CD_UID, UID);
    }

    // Workaround for
    // http://sourceware.org/bugzilla/show_bug.cgi?id=9622
    unsetenv("TERM");
    putenv((char*)"TERM=dumb");

    char *args[21];
    args[0] = (char*)"gdb";
    args[1] = (char*)"-batch";

    // when/if gdb supports it:
    // (https://bugzilla.redhat.com/show_bug.cgi?id=528668):
    args[2] = (char*)"-ex";
    string dfd = "set debug-file-directory /usr/lib/debug";
    const char *p = pDebugInfoDirs;
    while (1)
    {
        const char *colon_or_nul = strchrnul(p, ':');
        dfd += ':';
        dfd.append(p, colon_or_nul - p);
        dfd += "/usr/lib/debug";
        if (*colon_or_nul != ':')
            break;
        p = colon_or_nul + 1;
    }
    args[3] = (char*)dfd.c_str();

    /* "file BINARY_FILE" is needed, without it gdb cannot properly
     * unwind the stack. Currently the unwind information is located
     * in .eh_frame which is stored only in binary, not in coredump
     * or debuginfo.
     *
     * Fedora GDB does not strictly need it, it will find the binary
     * by its build-id.  But for binaries either without build-id
     * (= built on non-Fedora GCC) or which do not have
     * their debuginfo rpm installed gdb would not find BINARY_FILE
     * so it is still makes sense to supply "file BINARY_FILE".
     *
     * Unfortunately, "file BINARY_FILE" doesn't work well if BINARY_FILE
     * was deleted (as often happens during system updates):
     * gdb uses specified BINARY_FILE
     * even if it is completely unrelated to the coredump.
     * See https://bugzilla.redhat.com/show_bug.cgi?id=525721
     *
     * TODO: check mtimes on COREFILE and BINARY_FILE and not supply
     * BINARY_FILE if it is newer (to at least avoid gdb complaining).
     */
    args[4] = (char*)"-ex";
    string file = ssprintf("file %s", executable.c_str());
    args[5] = (char*)file.c_str();

    args[6] = (char*)"-ex";
    string corefile = ssprintf("core-file %s/"FILENAME_COREDUMP, pDebugDumpDir);
    args[7] = (char*)corefile.c_str();

    args[8] = (char*)"-ex";
    /*args[9] = ... see below */
    args[10] = (char*)"-ex";
    args[11] = (char*)"info sharedlib";
    /* glibc's abort() stores its message in __abort_msg variable */
    args[12] = (char*)"-ex";
    args[13] = (char*)"print (char*)__abort_msg";
    args[14] = (char*)"-ex";
    args[15] = (char*)"print (char*)__glib_assert_msg";
    args[16] = (char*)"-ex";
    args[17] = (char*)"info registers";
    args[18] = (char*)"-ex";
    args[19] = (char*)"disassemble";
    args[20] = NULL;

    /* Get the backtrace, but try to cap its size */
    /* Limit bt depth. With no limit, gdb sometimes OOMs the machine */
    unsigned bt_depth = 2048;
    const char *thread_apply_all = "thread apply all ";
    const char *full = " full";
    while (1)
    {
        string cmd = ssprintf("%sbacktrace %u%s", thread_apply_all, bt_depth, full);
        args[9] = (char*)cmd.c_str();
        pBacktrace = "";
        ExecVP(args, xatoi_u(UID.c_str()), /*redirect_stderr:*/ 1, pBacktrace);
        if (bt_depth <= 64 || pBacktrace.size() < 256*1024)
            return;
        bt_depth /= 2;
        if (bt_depth <= 64 && thread_apply_all[0] != '\0')
        {
            /* This program likely has gazillion threads, dont try to bt them all */
            bt_depth = 256;
            thread_apply_all = "";
        }
        if (bt_depth <= 64 && full[0] != '\0')
        {
            /* Looks like there are gigantic local structures or arrays, disable "full" bt */
            bt_depth = 256;
            full = "";
        }
    }
}

static void GetIndependentBuildIdPC(const char *unstrip_n_output,
                                    string& pIndependentBuildIdPC)
{
    // lines look like this:
    // 0x400000+0x209000 23c77451cf6adff77fc1f5ee2a01d75de6511dda@0x40024c - - [exe]
    // 0x400000+0x209000 ab3c8286aac6c043fd1bb1cc2a0b88ec29517d3e@0x40024c /bin/sleep /usr/lib/debug/bin/sleep.debug [exe]
    // 0x7fff313ff000+0x1000 389c7475e3d5401c55953a425a2042ef62c4c7df@0x7fff313ff2f8 . - linux-vdso.so.1
    const char *line = unstrip_n_output;
    while (*line)
    {
        const char *eol = strchrnul(line, '\n');
        const char *plus = (char*)memchr(line, '+', eol - line);
        if (plus)
        {
            while (++plus < eol && *plus != '@')
            {
                if (!isspace(*plus))
                {
                    pIndependentBuildIdPC += *plus;
                }
            }
        }
        if (*eol != '\n') break;
        line = eol + 1;
    }
}

static string run_unstrip_n(const char *pDebugDumpDir)
{
    string UID;
    {
        CDebugDump dd;
        dd.Open(pDebugDumpDir);
        dd.LoadText(CD_UID, UID);
    }

    char* args[4];
    args[0] = (char*)"eu-unstrip";
    args[1] = xasprintf("--core=%s/"FILENAME_COREDUMP, pDebugDumpDir);
    args[2] = (char*)"-n";
    args[3] = NULL;

    string output;
    ExecVP(args, xatoi_u(UID.c_str()), /*redirect_stderr:*/ 0, output);

    free(args[1]);

    return output;
}

/* Needs gdb feature from here: https://bugzilla.redhat.com/show_bug.cgi?id=528668
 * It is slated to be in F12/RHEL6.
 */
static void InstallDebugInfos(const char *pDebugDumpDir,
                              const char *debuginfo_dirs,
                              string& build_ids)
{
    update_client(_("Starting debuginfo installation"));

    int pipeout[2]; //TODO: can we use ExecVP?
    xpipe(pipeout);

    fflush(NULL);
    pid_t child = fork();
    if (child < 0)
    {
        /*close(pipeout[0]); - why bother */
        /*close(pipeout[1]); */
        perror_msg_and_die("fork");
    }
    if (child == 0)
    {
        close(pipeout[0]);
        xmove_fd(pipeout[1], STDOUT_FILENO);
        xmove_fd(xopen("/dev/null", O_RDONLY), STDIN_FILENO);

        char *coredump = xasprintf("%s/"FILENAME_COREDUMP, pDebugDumpDir);
        /* SELinux guys are not happy with /tmp, using /var/run/abrt */
        char *tempdir = xasprintf(LOCALSTATEDIR"/run/abrt/tmp-%lu-%lu", (long)getpid(), (long)time(NULL));
        /* log() goes to stderr/syslog, it's ok to use it here */
        VERB1 log("Executing: %s %s %s %s", "abrt-debuginfo-install", coredump, tempdir, debuginfo_dirs);
        /* We want parent to see errors in the same stream */
        xdup2(STDOUT_FILENO, STDERR_FILENO);
        execlp("abrt-debuginfo-install", "abrt-debuginfo-install", coredump, tempdir, debuginfo_dirs, NULL);
        perror_msg("Can't execute '%s'", "abrt-debuginfo-install");
        /* Serious error (1 means "some debuginfos not found") */
        exit(2);
    }

    close(pipeout[1]);

    FILE *pipeout_fp = fdopen(pipeout[0], "r");
    if (pipeout_fp == NULL) /* never happens */
    {
        close(pipeout[0]);
        waitpid(child, NULL, 0);
        return;
    }

    char buff[1024];
    while (fgets(buff, sizeof(buff), pipeout_fp))
    {
        strchrnul(buff, '\n')[0] = '\0';

        if (strncmp(buff, "MISSING:", 8) == 0)
        {
            build_ids += "Debuginfo absent: ";
            build_ids += buff + 8;
            build_ids += "\n";
            continue;
        }

        const char *p = buff;
        while (*p == ' ' || *p == '\t')
        {
            p++;
        }
        if (*p)
        {
            VERB1 log("%s", buff);
            update_client("%s", buff);
        }
    }
    fclose(pipeout_fp);

    int status = 0;
    while (waitpid(child, &status, 0) < 0 && errno == EINTR)
        continue;
    if (WIFEXITED(status))
    {
        if (WEXITSTATUS(status) > 1)
            error_msg("%s exited with %u", "abrt-debuginfo-install", (int)WEXITSTATUS(status));
    }
    else
    {
        error_msg("%s killed by signal %u", "abrt-debuginfo-install", (int)WTERMSIG(status));
    }
}

static double get_dir_size(const char *dirname,
                           string *worst_file,
                           double *maxsz)
{
    DIR *dp = opendir(dirname);
    if (dp == NULL)
        return 0;

    struct dirent *ep;
    struct stat stats;
    double size = 0;
    while ((ep = readdir(dp)) != NULL)
    {
        if (dot_or_dotdot(ep->d_name))
            continue;
        string dname = concat_path_file(dirname, ep->d_name);
        if (lstat(dname.c_str(), &stats) != 0)
            continue;
        if (S_ISDIR(stats.st_mode))
        {
            double sz = get_dir_size(dname.c_str(), worst_file, maxsz);
            size += sz;
        }
        else if (S_ISREG(stats.st_mode))
        {
            double sz = stats.st_size;
            size += sz;

            if (worst_file)
            {
                /* Calculate "weighted" size and age
                 * w = sz_kbytes * age_mins */
                sz /= 1024;
                long age = (time(NULL) - stats.st_mtime) / 60;
                if (age > 0)
                    sz *= age;

                if (sz > *maxsz)
                {
                    *maxsz = sz;
                    *worst_file = dname;
                }
            }
        }
    }
    closedir(dp);
    return size;
}

static void trim_debuginfo_cache(unsigned max_mb)
{
    while (1)
    {
        string worst_file;
        double maxsz = 0;
        double cache_sz = get_dir_size(DEBUGINFO_CACHE_DIR, &worst_file, &maxsz);
        if (cache_sz / (1024 * 1024) < max_mb)
            break;
        VERB1 log("%s is %.0f bytes (over %u MB), deleting '%s'",
                DEBUGINFO_CACHE_DIR, cache_sz, max_mb, worst_file.c_str());
        if (unlink(worst_file.c_str()) != 0)
            perror_msg("Can't unlink '%s'", worst_file.c_str());
    }
}

string CAnalyzerCCpp::GetLocalUUID(const char *pDebugDumpDir)
{
    string executable;
    string package;
    {
        CDebugDump dd;
        dd.Open(pDebugDumpDir);
        dd.LoadText(FILENAME_EXECUTABLE, executable);
        dd.LoadText(FILENAME_PACKAGE, package);
    }

    string unstrip_n_output = run_unstrip_n(pDebugDumpDir);
    string independentBuildIdPC;
    GetIndependentBuildIdPC(unstrip_n_output.c_str(), independentBuildIdPC);

    /* package variable has "firefox-3.5.6-1.fc11[.1]" format */
    /* Remove distro suffix and maybe least significant version number */
    char *trimmed_package = xstrdup(package.c_str());
    char *p = trimmed_package;
    while (*p)
    {
        if (*p == '.' && (p[1] < '0' || p[1] > '9'))
        {
            /* We found "XXXX.nondigitXXXX", trim this part */
            *p = '\0';
            break;
        }
        p++;
    }
    char *first_dot = strchr(trimmed_package, '.');
    if (first_dot)
    {
        char *last_dot = strrchr(first_dot, '.');
        if (last_dot != first_dot)
        {
            /* There are more than one dot: "1.2.3"
             * Strip last part, we don't want to distinquish crashes
             * in packages which differ only by minor release number.
             */
            *last_dot = '\0';
        }
    }
    string hash_str = trimmed_package + executable + independentBuildIdPC;
    free(trimmed_package);
    return create_hash(hash_str.c_str());
}

string CAnalyzerCCpp::GetGlobalUUID(const char *pDebugDumpDir)
{
    CDebugDump dd;
    dd.Open(pDebugDumpDir);
    if (dd.Exist(FILENAME_GLOBAL_UUID))
    {
        string uuid;
        dd.LoadText(FILENAME_GLOBAL_UUID, uuid);
        return uuid;
    }
    else
    {
        // Compatibility code.
        // This whole block should be deleted for Fedora 14.
        log(_("Getting global universal unique identification..."));

        string backtrace_path = concat_path_file(pDebugDumpDir, FILENAME_BACKTRACE);
        string executable;
        string package;
        string uid_str;
        dd.LoadText(FILENAME_EXECUTABLE, executable);
        dd.LoadText(FILENAME_PACKAGE, package);
        if (m_bBacktrace)
            dd.LoadText(CD_UID, uid_str);

        string independent_backtrace;
        if (m_bBacktrace)
        {
            /* Run abrt-backtrace to get independent backtrace suitable
               to UUID calculation. */
            char *args[7];
            args[0] = (char*)"abrt-backtrace";
            args[1] = (char*)"--single-thread";
            args[2] = (char*)"--remove-exit-handlers";
            args[3] = (char*)"--frame-depth=5";
            args[4] = (char*)"--remove-noncrash-frames";
            args[5] = (char*)backtrace_path.c_str();
            args[6] = NULL;

            int pipeout[2];
            xpipe(pipeout); /* stdout of abrt-backtrace */

            fflush(NULL);
            pid_t child = fork();
            if (child == -1)
                perror_msg_and_die("fork");
            if (child == 0)
            {
                VERB1 log("Executing %s", args[0]);

                xmove_fd(pipeout[1], STDOUT_FILENO);
                close(pipeout[0]); /* read side of the pipe */

                /* abrt-backtrace is executed under the user's uid and gid. */
                uid_t uid = xatoi_u(uid_str.c_str());
                struct passwd* pw = getpwuid(uid);
                gid_t gid = pw ? pw->pw_gid : uid;
                setgroups(1, &gid);
                xsetregid(gid, gid);
                xsetreuid(uid, uid);

                execvp(args[0], args);
                VERB1 perror_msg("Can't execute '%s'", args[0]);
                exit(1);
            }

            close(pipeout[1]); /* write side of the pipe */

            /* Read the result from abrt-backtrace. */
            int r;
            char buff[1024];
            while ((r = safe_read(pipeout[0], buff, sizeof(buff) - 1)) > 0)
            {
                buff[r] = '\0';
                independent_backtrace += buff;
            }
            close(pipeout[0]);

            /* Wait until it exits, and check the exit status. */
            errno = 0;
            int status;
            waitpid(child, &status, 0);
            if (!WIFEXITED(status))
            {
                perror_msg("abrt-backtrace not executed properly, "
                           "status: %x signal: %d", status, WIFSIGNALED(status));
            }
            else
            {
                int exit_status = WEXITSTATUS(status);
                if (exit_status == 79) /* EX_PARSINGFAILED */
                {
                    /* abrt-backtrace returns alternative backtrace
                       representation in this case, so everything will work
                       as expected except worse duplication detection */
                    log_msg("abrt-backtrace failed to parse the backtrace");
                }
                else if (exit_status == 80) /* EX_THREADDETECTIONFAILED */
                {
                    /* abrt-backtrace returns backtrace with all threads
                       in this case, so everything will work as expected
                       except worse duplication detection */
                    log_msg("abrt-backtrace failed to determine crash frame");
                }
                else if (exit_status != 0)
                {
                    /* this is unexpected problem and it should be investigated */
                    error_msg("abrt-backtrace run failed, exit value: %d",
                              exit_status);
                }
            }

            /*VERB1 log("abrt-backtrace result: %s", independent_backtrace.c_str());*/
        }
        /* else: no backtrace, independent_backtrace == "" */

        string hash_base = package + executable + independent_backtrace;
        return create_hash(hash_base.c_str());
    }
}

static bool DebuginfoCheckPolkit(uid_t uid)
{
    fflush(NULL);
    int child_pid = fork();
    if (child_pid < 0)
    {
        perror_msg_and_die("fork");
    }
    if (child_pid == 0)
    {
        //child
        xsetreuid(uid, uid);
        PolkitResult result = polkit_check_authorization(getpid(),
                 "org.fedoraproject.abrt.install-debuginfos");
        exit(result != PolkitYes); //exit 1 (failure) if not allowed
    }

    //parent
    int status;
    if (waitpid(child_pid, &status, 0) > 0
     && WIFEXITED(status)
     && WEXITSTATUS(status) == 0
    ) {
        return true; //authorization OK
    }
    log("UID %d is not authorized to install debuginfos", uid);
    return false;
}

void CAnalyzerCCpp::CreateReport(const char *pDebugDumpDir, int force)
{
    string package, executable, UID;

    CDebugDump dd;
    dd.Open(pDebugDumpDir);

    if (!m_bBacktrace)
        return;

    if (!force)
    {
        bool bt_exists = dd.Exist(FILENAME_BACKTRACE);
        if (bt_exists)
            return; /* backtrace already exists */
    }

    dd.LoadText(FILENAME_PACKAGE, package);
    dd.LoadText(FILENAME_EXECUTABLE, executable);
    dd.LoadText(CD_UID, UID);
    dd.Close(); /* do not keep dir locked longer than needed */

    string build_ids;
    if (m_bInstallDebugInfo && DebuginfoCheckPolkit(xatoi_u(UID.c_str())))
    {
        if (m_nDebugInfoCacheMB > 0)
            trim_debuginfo_cache(m_nDebugInfoCacheMB);
        InstallDebugInfos(pDebugDumpDir, m_sDebugInfoDirs.c_str(), build_ids);
    }
    else
        VERB1 log(_("Skipping debuginfo installation"));

    /* Create and store backtrace. */
    string backtrace_str;
    GetBacktrace(pDebugDumpDir, m_sDebugInfoDirs.c_str(), backtrace_str);
    dd.Open(pDebugDumpDir);
    dd.SaveText(FILENAME_BACKTRACE, (backtrace_str + build_ids).c_str());

    if (m_bMemoryMap)
        dd.SaveText(FILENAME_MEMORYMAP, "memory map of the crashed C/C++ application, not implemented yet");

    /* Compute and store UUID from the backtrace. */
    char *backtrace_cpy = xstrdup(backtrace_str.c_str());
    struct backtrace *backtrace = backtrace_parse(backtrace_cpy, false, false);
    free(backtrace_cpy);
    if (backtrace)
    {
        /* Get the quality of the full backtrace. */
        float q1 = backtrace_quality(backtrace);

        /* Remove all the other threads except the crash thread. */
        struct thread *crash_thread = backtrace_find_crash_thread(backtrace);
        if (crash_thread)
            backtrace_remove_threads_except_one(backtrace, crash_thread);
        else
            log_msg("Detection of crash thread failed.\n");

        /* Get the quality of the crash thread. */
        float q2 = backtrace_quality(backtrace);

        backtrace_remove_noncrash_frames(backtrace);

        /* Do the frame removal now. */
        backtrace_limit_frame_depth(backtrace, 5);
        /* Frame removal can be done before removing exit handlers. */
        backtrace_remove_exit_handlers(backtrace);

        /* Get the quality of frames around the crash. */
        float q3 = backtrace_quality(backtrace);

        /* Compute UUID. */
        struct strbuf *bt = backtrace_tree_as_str(backtrace, false);
        strbuf_prepend_str(bt, executable.c_str());
        strbuf_prepend_str(bt, package.c_str());
        dd.SaveText(FILENAME_GLOBAL_UUID, create_hash(bt->buf).c_str());
        strbuf_free(bt);

        /* Compute and store backtrace rating. */
        /* Compute and store backtrace rating. The crash frame
           is more important that the others. The frames around
           the crash are more important than the rest.  */
        float qtot = 0.25f * q1 + 0.35f * q2 + 0.4f * q3;

        /* Turn the quality to rating. */
        const char *rating;
        if (qtot < 0.6f)      rating = "0";
        else if (qtot < 0.7f) rating = "1";
        else if (qtot < 0.8f) rating = "2";
        else if (qtot < 0.9f) rating = "3";
        else                  rating = "4";
        dd.SaveText(FILENAME_RATING, rating);

        /* Get the function name from the crash frame. */
        if (crash_thread)
        {
            struct frame *abort_frame = thread_find_abort_frame(crash_thread);
            if (abort_frame)
            {
                struct frame *crash_frame = abort_frame->next;
                if (crash_frame && crash_frame->function && 0 != strcmp(crash_frame->function, "??"))
                    dd.SaveText(FILENAME_CRASH_FUNCTION, crash_frame->function);
            }
        }

        backtrace_free(backtrace);
    }
    else
    {
        /* If the parser failed fall back to the independent backtrace. */
        /* If we write and use a hand-written parser instead of the bison one,
           the parser never fails, and it will be possible to get rid of
           the independent_backtrace and backtrace_rate_old. */
        struct strbuf *ibt = independent_backtrace(backtrace_str.c_str());
        strbuf_prepend_str(ibt, executable.c_str());
        strbuf_prepend_str(ibt, package.c_str());
        dd.SaveText(FILENAME_GLOBAL_UUID, create_hash(ibt->buf).c_str());
        strbuf_free(ibt);

        /* Compute and store backtrace rating. */
        /* Crash frame is not known so store nothing. */
        dd.SaveText(FILENAME_RATING, to_string(backtrace_rate_old(backtrace_str.c_str())).c_str());
    }

    dd.Close();
}

/*
 this is just a workaround until kernel changes it's behavior
 when handling pipes in core_pattern
*/
#ifdef HOSTILE_KERNEL
#define CORE_SIZE_PATTERN "Max core file size=1:unlimited"
static int isdigit_str(char *str)
{
    do {
        if (*str < '0' || *str > '9')
            return 0;
    } while (*++str);
    return 1;
}

static int set_limits()
{
    DIR *dir = opendir("/proc");
    if (!dir) {
        /* this shouldn't fail, but to be safe.. */
        return 1;
    }

    struct dirent *ent;
    while ((ent = readdir(dir)) != NULL) {
        if (!isdigit_str(ent->d_name))
            continue;

        char limits_name[sizeof("/proc/%s/limits") + sizeof(int)];
        snprintf(limits_name, sizeof(limits_name), "/proc/%s/limits", ent->d_name);
        FILE *limits_fp = fopen(limits_name, "r");
        if (!limits_fp) {
            break;
        }

        char line[128];
        char *ulimit_c = NULL;
        while (1) {
            if (fgets(line, sizeof(line)-1, limits_fp) == NULL)
                break;
            if (strncmp(line, "Max core file size", sizeof("Max core file size")-1) == 0) {
                ulimit_c = skip_whitespace(line + sizeof("Max core file size")-1);
                skip_non_whitespace(ulimit_c)[0] = '\0';
                break;
            }
        }
        fclose(limits_fp);
        if (!ulimit_c || ulimit_c[0] != '0' || ulimit_c[1] != '\0') {
            /*process has nonzero ulimit -c, so need to modify it*/
            continue;
        }
        /* echo -n 'Max core file size=1:unlimited' >/proc/PID/limits */
        int fd = open(limits_name, O_WRONLY);
        if (fd >= 0) {
            errno = 0;
            /*full_*/
            ssize_t n = write(fd, CORE_SIZE_PATTERN, sizeof(CORE_SIZE_PATTERN)-1);
            if (n < sizeof(CORE_SIZE_PATTERN)-1)
                log("warning: can't write core_size limit to: %s", limits_name);
            close(fd);
        }
        else
        {
            log("warning: can't open %s for writing", limits_name);
        }
    }
    closedir(dir);
    return 0;
}
#endif /* HOSTILE_KERNEL */

void CAnalyzerCCpp::Init()
{
    FILE *fp = fopen(CORE_PATTERN_IFACE, "r");
    if (fp)
    {
        char line[PATH_MAX];
        if (fgets(line, sizeof(line), fp))
            m_sOldCorePattern = line;
        fclose(fp);
    }
    if (m_sOldCorePattern[0] == '|')
    {
        if (m_sOldCorePattern == CORE_PATTERN)
        {
            log("warning: %s already contains %s, "
                "did abrt daemon crash recently?",
                CORE_PATTERN_IFACE, CORE_PATTERN);
            /* There is no point in "restoring" CORE_PATTERN_IFACE
             * to CORE_PATTERN on exit. Will restore to a default value:
             */
            m_sOldCorePattern = "core";
        } else {
            log("warning: %s was already set to run a crash analyser (%s), "
                "abrt may interfere with it",
                CORE_PATTERN_IFACE, CORE_PATTERN);
        }
    }
#ifdef HOSTILE_KERNEL
    if (set_limits() != 0)
        log("warning: failed to set core_size limit, ABRT won't detect crashes in"
            "compiled apps");
#endif

    fp = fopen(CORE_PATTERN_IFACE, "w");
    if (fp)
    {
        fputs(CORE_PATTERN, fp);
        fclose(fp);
    }

    /* read the core_pipe_limit and change it if it's == 0
       otherwise the abrt-hook-ccpp won't be able to read /proc/<pid>
       of the crashing process
    */
    fp = fopen(CORE_PIPE_LIMIT_IFACE, "r");
    if (fp)
    {
        /* we care only about the first char, if it's
            not '0' then we don't have to change it,
            because it means that it's already != 0
        */
        char pipe_limit[2];
        if (fgets(pipe_limit, sizeof(pipe_limit), fp))
            m_sOldCorePipeLimit = pipe_limit;
        fclose(fp);
        if(m_sOldCorePipeLimit[0] == '0')
        {
            fp = fopen(CORE_PIPE_LIMIT_IFACE, "w");
            if(fp)
            {
                fputs(CORE_PIPE_LIMIT, fp);
                fclose(fp);
            }
            else
            {
                log("warning: failed to set core_pipe_limit, ABRT won't detect"
                    "crashes in compiled apps if kernel > 2.6.31");
            }
        }
    }
}

void CAnalyzerCCpp::DeInit()
{
    /* no need to restore the core_pipe_limit, because it's only used
       when there is s pipe in core_pattern
    */
    FILE *fp = fopen(CORE_PATTERN_IFACE, "w");
    if (fp)
    {
        fputs(m_sOldCorePattern.c_str(), fp);
        fclose(fp);
    }
}

void CAnalyzerCCpp::SetSettings(const map_plugin_settings_t& pSettings)
{
    m_pSettings = pSettings;

    map_plugin_settings_t::const_iterator end = pSettings.end();
    map_plugin_settings_t::const_iterator it;
    it = pSettings.find("Backtrace");
    if (it != end)
    {
        m_bBacktrace = string_to_bool(it->second.c_str());
    }
    it = pSettings.find("MemoryMap");
    if (it != end)
    {
        m_bMemoryMap = string_to_bool(it->second.c_str());
    }
    it = pSettings.find("DebugInfo");
    if (it != end)
    {
        m_sDebugInfo = it->second;
    }
    it = pSettings.find("DebugInfoCacheMB");
    if (it != end)
    {
        m_nDebugInfoCacheMB = xatou(it->second.c_str());
    }
    it = pSettings.find("InstallDebugInfo");
    if (it == end) //compat, remove after 0.0.11
        it = pSettings.find("InstallDebuginfo");
    if (it != end)
    {
        m_bInstallDebugInfo = string_to_bool(it->second.c_str());
    }
    m_sDebugInfoDirs = DEBUGINFO_CACHE_DIR;
    it = pSettings.find("ReadonlyLocalDebugInfoDirs");
    if (it != end)
    {
        m_sDebugInfoDirs += ':';
        m_sDebugInfoDirs += it->second;
    }
}

//ok to delete?
//const map_plugin_settings_t& CAnalyzerCCpp::GetSettings()
//{
//    m_pSettings["MemoryMap"] = m_bMemoryMap ? "yes" : "no";
//    m_pSettings["DebugInfo"] = m_sDebugInfo;
//    m_pSettings["DebugInfoCacheMB"] = to_string(m_nDebugInfoCacheMB);
//    m_pSettings["InstallDebugInfo"] = m_bInstallDebugInfo ? "yes" : "no";
//
//    return m_pSettings;
//}

PLUGIN_INFO(ANALYZER,
            CAnalyzerCCpp,
            "CCpp",
            "0.0.1",
            "Analyzes crashes in C/C++ programs",
            "zprikryl@redhat.com",
            "https://fedorahosted.org/abrt/wiki",
            "");