/* -*- Mode: C; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
 * This file is part of the LibreOffice project.
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */

#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <time.h>

#include <dlfcn.h>
#include <fcntl.h>
#include <pthread.h>
#include <sys/mman.h>
#include <unistd.h>

#include <jni.h>
#include <zlib.h>

#include <android/log.h>

#include "uthash.h"

#include <osl/detail/android-bootstrap.h>

#undef LOGI

#define LOGI(...) ((void)__android_log_print(ANDROID_LOG_INFO, "lo-bootstrap", __VA_ARGS__))
#define LOGE(...) ((void)__android_log_print(ANDROID_LOG_ERROR, "lo-bootstrap", __VA_ARGS__))

#define MAX(a,b) ((a) > (b) ? (a) : (b))

struct engine {
    int dummy;
};

/* These are valid / used in all apps. */
const char *data_dir;
const char *cache_dir;
void *apk_file;
int apk_file_size;
JavaVM *the_java_vm;

/* Zip data structures */

/* compression methods */
#define STORE    0

struct local_file_header {
    uint32_t signature;
    uint16_t min_version;
    uint16_t general_flag;
    uint16_t compression;
    uint16_t lastmod_time;
    uint16_t lastmod_date;
    uint32_t crc32;
    uint32_t compressed_size;
    uint32_t uncompressed_size;
    uint16_t filename_size;
    uint16_t extra_field_size;
    char     data[0];
} __attribute__((__packed__));

struct cdir_entry {
    uint32_t signature;
    uint16_t creator_version;
    uint16_t min_version;
    uint16_t general_flag;
    uint16_t compression;
    uint16_t lastmod_time;
    uint16_t lastmod_date;
    uint32_t crc32;
    uint32_t compressed_size;
    uint32_t uncompressed_size;
    uint16_t filename_size;
    uint16_t extra_field_size;
    uint16_t file_comment_size;
    uint16_t disk_num;
    uint16_t internal_attr;
    uint32_t external_attr;
    uint32_t offset;
    char     data[0];
} __attribute__((__packed__));

#define CDIR_END_SIG 0x06054b50

struct cdir_end {
    uint32_t signature;
    uint16_t disk_num;
    uint16_t cdir_disk;
    uint16_t disk_entries;
    uint16_t cdir_entries;
    uint32_t cdir_size;
    uint32_t cdir_offset;
    uint16_t comment_size;
    char     comment[0];
} __attribute__((__packed__));

/* End of Zip data structures */

static struct cdir_entry *cdir_start;
static uint16_t cdir_entries;

/* Data structure to turn Zip's list in arbitrary order of
 * hierarchical pathnames (not necessarily including entries for
 * directories) into an actual hierarchical directory tree, so that we
 * can iterate over directory entries properly in the dirent style
 * functions.
 */

typedef struct direntry *direntry;

struct direntry {
    UT_hash_handle hh;
    enum { REGULAR, DIRECTORY } kind;
    int ino;
    union {
        struct cdir_entry *file;
        direntry subdir;
    };
};

struct lo_apk_dir {
    direntry cur;
};

static direntry assets = NULL;

static uint32_t
cdir_entry_size(struct cdir_entry *entry)
{
    return sizeof(*entry) +
        letoh16(entry->filename_size) +
        letoh16(entry->extra_field_size) +
        letoh16(entry->file_comment_size);
}

int
setup_cdir(void)
{
    struct cdir_end *dirend = (struct cdir_end *)((char *) apk_file + apk_file_size - sizeof(*dirend));
    uint32_t cdir_offset;

    while ((void *)dirend > apk_file &&
           letoh32(dirend->signature) != CDIR_END_SIG)
        dirend = (struct cdir_end *)((char *)dirend - 1);
    if (letoh32(dirend->signature) != CDIR_END_SIG) {
        LOGE("setup_cdir: Could not find end of central directory record");
        return 0;
    }

    cdir_offset = letoh32(dirend->cdir_offset);

    cdir_entries = letoh16(dirend->cdir_entries);
    cdir_start = (struct cdir_entry *)((char *)apk_file + cdir_offset);

    return 1;
}

static struct cdir_entry *
find_cdir_entry(struct cdir_entry *entry, int count, const char *name)
{
    size_t name_size = strlen(name);
    while (count--) {
        if (letoh16(entry->filename_size) == name_size &&
            !memcmp(entry->data, name, name_size))
            return entry;
        entry = (struct cdir_entry *)((char *)entry + cdir_entry_size(entry));
    }
    return NULL;
}

static void
handle_one_asset(struct cdir_entry *entry)
{
    /* In the .apk there are no initial slashes */
    const char *p = entry->data + sizeof("assets/")-1;
    const char *z = entry->data + entry->filename_size;
    direntry *dir = &assets;
    static int ino = 1;

    while (p < z) {
        const char *q = p;
        direntry old, new;

        while (q < z && *q != '/')
            q++;
        HASH_FIND(hh, *dir, p, (unsigned)(q - p), old);
        if (*q == '/') {
            if (old == NULL) {
                new = malloc(sizeof(*new));
                new->ino = ino++;
                new->kind = DIRECTORY;
                new->subdir = NULL;
                HASH_ADD_KEYPTR(hh, *dir, p, (unsigned)(q - p), new);
                dir = &new->subdir;
            } else {
                dir = &old->subdir;
            }
            p = q + 1;
        } else {
            if (old == NULL) {
                new = malloc(sizeof(*new));
                new->ino = ino++;
                new->kind = REGULAR;
                new->file = entry;
                HASH_ADD_KEYPTR(hh, *dir, p, (unsigned)(q - p), new);
            } else {
                LOGE("duplicate entry in apk: %.*s", entry->filename_size, entry->data);
            }
            p = q;
        }
        (void) dir;
    }
}

int
setup_assets_tree(void)
{
    int count = cdir_entries;
    struct cdir_entry *entry = cdir_start;

    while (count--) {
        if (letoh16(entry->filename_size) >= sizeof("assets/")-1 &&
            memcmp(entry->data, "assets/", sizeof("assets/")-1) == 0)
            handle_one_asset(entry);
        entry = (struct cdir_entry *)((char *)entry + cdir_entry_size(entry));
    }
    return 1;
}

/* The lo-native-code shared library is always loaded from Java, so this is
 * always called by JNI first.
 */
__attribute__ ((visibility("default")))
jint
JNI_OnLoad(JavaVM* vm, void* reserved)
{
    (void) reserved;

    the_java_vm = vm;

    return JNI_VERSION_1_6;
}

// public static native boolean setup(String dataDir,
//                                    String cacheDir,
//                                    String apkFile)

__attribute__ ((visibility("default")))
jboolean
Java_org_libreoffice_android_Bootstrap_setup__Ljava_lang_String_2Ljava_lang_String_2Ljava_lang_String_2
    (JNIEnv* env,
     jobject clazz,
     jstring dataDir,
     jstring cacheDir,
     jstring apkFile)
{
    struct stat st;
    int fd;
    const char *dataDirPath;
    const char *cacheDirPath;
    const char *apkFilePath;

    (void) clazz;

    dataDirPath = (*env)->GetStringUTFChars(env, dataDir, NULL);
    data_dir = strdup(dataDirPath);
    (*env)->ReleaseStringUTFChars(env, dataDir, dataDirPath);

    cacheDirPath = (*env)->GetStringUTFChars(env, cacheDir, NULL);
    cache_dir = strdup(cacheDirPath);
    (*env)->ReleaseStringUTFChars(env, cacheDir, cacheDirPath);

    apkFilePath =  (*env)->GetStringUTFChars(env, apkFile, NULL);

    fd = open(apkFilePath, O_RDONLY);
    if (fd == -1) {
        LOGE("Could not open %s", apkFilePath);
        (*env)->ReleaseStringUTFChars(env, apkFile, apkFilePath);
        return JNI_FALSE;
    }
    if (fstat(fd, &st) == -1) {
        LOGE("Could not fstat %s", apkFilePath);
        close(fd);
        (*env)->ReleaseStringUTFChars(env, apkFile, apkFilePath);
        return JNI_FALSE;
    }
    apk_file = mmap(NULL, st.st_size, PROT_READ, MAP_SHARED, fd, 0);
    close(fd);

    if (apk_file == MAP_FAILED) {
        LOGE("Could not mmap %s", apkFilePath);
        (*env)->ReleaseStringUTFChars(env, apkFile, apkFilePath);
        return JNI_FALSE;
    }
    apk_file_size = st.st_size;

    (*env)->ReleaseStringUTFChars(env, apkFile, apkFilePath);

    if (!setup_cdir())
        return JNI_FALSE;

    if (!setup_assets_tree())
        return JNI_FALSE;

    // Extract files from the .apk that can't be used mmapped directly from it
    extract_files(UNPACK_TREE, UNPACK_TREE, 0);
    extract_files(UNPACK_TREE_GZ, UNPACK_TREE_GZ, 1);

    return JNI_TRUE;
}

static jboolean
get_jni_string_array(JNIEnv *env,
                     const char *function_and_parameter_name,
                     jobject strv,
                     int *argc,
                     const char ***argv)
{
    jclass StringArray;
    int i;

    StringArray = (*env)->FindClass(env, "[Ljava/lang/String;");
    if (StringArray == NULL) {
        LOGE("Could not find String[] class");
        return JNI_FALSE;
    }

    if (!(*env)->IsInstanceOf(env, strv, StringArray)) {
        LOGE("%s is not a String[]?", function_and_parameter_name);
        return JNI_FALSE;
    }

    *argc = (*env)->GetArrayLength(env, strv);
    *argv = malloc(sizeof(char *) * (*argc+1));

    for (i = 0; i < *argc; i++) {
        const char *s = (*env)->GetStringUTFChars(env, (*env)->GetObjectArrayElement(env, strv, i), NULL);
        (*argv)[i] = strdup(s);
        (*env)->ReleaseStringUTFChars(env, (*env)->GetObjectArrayElement(env, strv, i), s);
    }
    (*argv)[*argc] = NULL;

    return JNI_TRUE;
}

// public static native int getpid();

__attribute__ ((visibility("default")))
jint
Java_org_libreoffice_android_Bootstrap_getpid(JNIEnv* env,
                                              jobject clazz)
{
    (void) env;
    (void) clazz;

    return getpid();
}

// public static native void system(String cmdline);

__attribute__ ((visibility("default")))
void
Java_org_libreoffice_android_Bootstrap_system(JNIEnv* env,
                                              jobject clazz,
                                              jstring cmdline)
{
    const char *s;

    (void) clazz;

    s = (*env)->GetStringUTFChars(env, cmdline, NULL);

    LOGI("system(%s)", s);

    system(s);

    (*env)->ReleaseStringUTFChars(env, cmdline, s);
}

// public static native void putenv(String string);

__attribute__ ((visibility("default")))
void
Java_org_libreoffice_android_Bootstrap_putenv(JNIEnv* env,
                                              jobject clazz,
                                              jstring string)
{
    const char *s;
    char *s_copy;

    (void) clazz;

    s = (*env)->GetStringUTFChars(env, string, NULL);
    s_copy = strdup(s);

    LOGI("putenv(%s)", s_copy);

    putenv(s_copy);

#if 0
    {
        static int beenhere=0;
        if (!beenhere) {
            LOGI("lo-bootstrap: Sleeping for 20 seconds, start ndk-gdb NOW if that is your intention");
            sleep(20);
            beenhere = 1;
        }
    }
#endif

    (*env)->ReleaseStringUTFChars(env, string, s);
}

__attribute__ ((visibility("default")))
void *
lo_apkentry(const char *filename,
            size_t *size)
{
    struct cdir_entry *entry;
    struct local_file_header *file;
    void *data;

    if (*filename == '/')
        filename++;

    entry = find_cdir_entry(cdir_start, cdir_entries, filename);

    if (entry == NULL) {
        LOGE("lo_apkentry: Could not find %s", filename);
        return NULL;
    }
    file = (struct local_file_header *)((char *)apk_file + letoh32(entry->offset));

    if (letoh16(file->compression) != STORE) {
        LOGE("lo_apkentry: File %s is compressed", filename);
        return NULL;
    }

    data = ((char *)&file->data) + letoh16(file->filename_size) + letoh16(file->extra_field_size);
    *size = file->uncompressed_size;

    /* LOGI("lo_apkentry(%s): %p, %d", filename, data, *size); */

    return data;
}

__attribute__ ((visibility("default")))
lo_apk_dir *
lo_apk_opendir(const char *dirname)
{
    /* In the .apk there are no initial slashes, but the parameter passed to
     * us does have it.
     */
    const char *p = dirname + sizeof("/assets/")-1;
    direntry dir = assets;

    if (!*p) {
        lo_apk_dir *result = malloc(sizeof(*result));
        result->cur = assets;
        return result;
    }

    while (1) {
        const char *q = p;
        direntry entry;

        while (*q && *q != '/')
            q++;

        HASH_FIND(hh, dir, p, (unsigned)(q - p), entry);

        if (entry == NULL && *q == '/') {
            errno = ENOENT;
            return NULL;
        } else if (entry == NULL) {
            /* Empty directories, or directories containing only "hidden"
             * files (like the .gitignore in sc/qa/unit/qpro/indeterminate)
             * are not present in the .apk. So we need to pretend that any
             * directory that doesn't exist as a parent of an entry in the
             * .apk *does* exist but is empty.
             */
            lo_apk_dir *result = malloc(sizeof(*result));
            result->cur = NULL;
            return result;
        }

        if (entry->kind != DIRECTORY) {
            errno = ENOTDIR;
            return NULL;
        }

        if (!q[0] || !q[1]) {
            lo_apk_dir *result = malloc(sizeof(*result));
            result->cur = entry->subdir;
            return result;
        }

        dir = entry->subdir;
        p = q + 1;
    }
}

__attribute__ ((visibility("default")))
struct dirent *
lo_apk_readdir(lo_apk_dir *dirp)
{
    static struct dirent result;

    if (dirp->cur == NULL) {
        /* LOGI("lo_apk_readdir(%p) = NULL", dirp); */
        return NULL;
    }

    result.d_ino = dirp->cur->ino;
    result.d_off = 0;
    result.d_reclen = 0;

    if (dirp->cur->kind == DIRECTORY)
        result.d_type = DT_DIR;
    else
        result.d_type = DT_REG;

    memcpy(result.d_name, dirp->cur->hh.key, dirp->cur->hh.keylen);
    result.d_name[dirp->cur->hh.keylen] = '\0';

    dirp->cur = dirp->cur->hh.next;

    /* LOGI("lo_apk_readdir(%p) = %s:%s", dirp, result.d_type == DT_DIR ? "DIR" : "REG", result.d_name); */

    return &result;
}

__attribute__ ((visibility("default")))
int
lo_apk_closedir(lo_apk_dir *dirp)
{
    free(dirp);

    /* LOGI("lo_apk_closedir(%p)", dirp); */

    return 0;
}

static int
new_stat(const char *path,
         struct stat *statp,
         struct cdir_entry *entry,
         int mode,
         int fake_ino)
{
    struct tm tm;

    memset(statp, 0, sizeof(*statp));
    statp->st_mode = mode | S_IRUSR;
    statp->st_nlink = 1;

    statp->st_uid = getuid();
    statp->st_gid = getgid();

    if (entry != NULL)
        statp->st_size = entry->uncompressed_size;
    else
        statp->st_size = 0;
    statp->st_blksize = 512;
    if (statp->st_size == 0)
        statp->st_blocks = 0;
    else
        statp->st_blocks = (statp->st_size - 1) / statp->st_blksize + 1;

    statp->st_atime = time(NULL);

    memset(&tm, 0, sizeof(tm));
    tm.tm_sec = (letoh16(entry->lastmod_time) & 0x1F) * 2;
    tm.tm_min = (letoh16(entry->lastmod_time) >> 5) & 0x3F;
    tm.tm_hour = (letoh16(entry->lastmod_time) >> 11) & 0x1F;
    tm.tm_mday = letoh16(entry->lastmod_date) & 0x1F;
    tm.tm_mon = ((letoh16(entry->lastmod_date) >> 5) & 0x0F) - 1;
    tm.tm_year = ((letoh16(entry->lastmod_date) >> 9) & 0x7F) + 80;

    statp->st_mtime = mktime(&tm);
    statp->st_ctime = statp->st_mtime;

    statp->st_ino = fake_ino;

    (void) path;
    /* LOGI("lo_apk_lstat(%s) = { mode=%o, size=%lld, ino=%lld mtime=%.24s }",
         path, statp->st_mode, statp->st_size, statp->st_ino,
         ctime((const time_t *) &statp->st_mtime)); */

    return 0;
}

__attribute__ ((visibility("default")))
int
lo_apk_lstat(const char *path,
             struct stat *statp)
{
    const char *pn = path;
    int count = cdir_entries;
    struct cdir_entry *entry = cdir_start;
    size_t name_size;

    if (*pn == '/') {
        pn++;
        if (!pn[0])
            return new_stat(path, statp, NULL, S_IFDIR | S_IXUSR, 1);
    }

    name_size = strlen(pn);
    while (count--)
    {
        if (letoh16(entry->filename_size) >= name_size &&
            !memcmp(entry->data, pn, name_size) &&
            (letoh16(entry->filename_size) == name_size || entry->data[name_size] == '/'))
            break;
        entry = (struct cdir_entry *)((char *)entry + cdir_entry_size(entry));
    }
    if (count >= 0) {
        if (letoh16(entry->filename_size) == name_size)
            return new_stat(path, statp, entry, S_IFREG, cdir_entries - count + 1);
        else
            return new_stat(path, statp, entry, S_IFDIR | S_IXUSR, cdir_entries - count + 1);
    }

    errno = ENOENT;
    return -1;
}

static int
mkdir_p(const char *dirname)
{
    char *p = malloc(strlen(dirname) + 1);
    const char *q = dirname + 1;
    const char *slash;

    do {
        slash = strchr(q, '/');
        if (slash == NULL)
            slash = q + strlen(q);
        memcpy(p, dirname, slash-dirname);
        p[slash-dirname] = '\0';
        if (mkdir(p, 0700) == -1 && errno != EEXIST) {
            LOGE("mkdir_p: Could not create %s: %s", p, strerror(errno));
            free(p);
            return 0;
        }
        if (*slash)
            q = slash + 1;
    } while (*slash);

    free(p);
    return 1;
}

static int
extract_gzipped(const char *filename,
                const char *apkentry,
                int size,
                FILE *f)
{
    gzFile gzfd;
    int gzerrno;
    int nbytes;
    char buf[5000];
    int total = 0;
    char *tmpname;
    FILE *tmp;

    tmpname = malloc(strlen(cache_dir) + strlen("/tmp.gz") + 1);
    strcpy(tmpname, cache_dir);
    strcat(tmpname, "/tmp.gz");

    tmp = fopen(tmpname, "w+");
    unlink(tmpname);

    if (tmp == NULL) {
        LOGE("extract_gzipped: could not create %s: %s", tmpname, strerror(errno));
        free(tmpname);
        return 0;
    }

    if (fwrite(apkentry, size, 1, tmp) != 1) {
        LOGE("extract_gzipped: could not write gzipped entry to %s: %s", tmpname, strerror(errno));
        fclose(tmp);
        free(tmpname);
        return 0;
    }

    free(tmpname);
    rewind(tmp);

    gzfd = gzdopen(fileno(tmp), "rb");
    if (gzfd == NULL) {
        LOGE("extract_gzipped: gzdopen failed");
        fclose(tmp);
        return 0;
    }

    while ((nbytes = gzread(gzfd, buf, sizeof(buf))) > 0) {
        fwrite(buf, nbytes, 1, f);
        total += nbytes;
    }
    if (nbytes == -1) {
        LOGE("extract_gzipped: Could not gzread from %s: %s", filename, gzerror(gzfd, &gzerrno));
        return total;
    }
    if (gzclose(gzfd) == -1) {
        LOGE("extract_gzipped: gzclose failed");
        return total;
    }

    return total;
}

void
extract_files(const char *root,
              const char *prefix,
              int gzipped)
{
    lo_apk_dir *tree = lo_apk_opendir(prefix);
    struct dirent *dent;

    if (tree == NULL)
        return;

    while ((dent = lo_apk_readdir(tree)) != NULL) {
        if (strcmp(dent->d_name, ".") == 0 ||
            strcmp(dent->d_name, "..") == 0)
            continue;

        if (dent->d_type == DT_DIR) {
            char *subdir = malloc(strlen(prefix) + 1 + strlen(dent->d_name) + 1);
            strcpy(subdir, prefix);
            strcat(subdir, "/");
            strcat(subdir, dent->d_name);
            extract_files(root, subdir, gzipped);
            free(subdir);
        } else {
            char *filename;
            char *newfilename;
            const char *apkentry;
            size_t size;
            struct stat st;
            FILE *f;

            filename = malloc(strlen(prefix) + 1 + strlen(dent->d_name) + 1);
            strcpy(filename, prefix);
            strcat(filename, "/");
            strcat(filename, dent->d_name);

            apkentry = lo_apkentry(filename, &size);
            if (apkentry == NULL) {
                LOGE("extract_files: Could not find %s in .apk", filename);
                free(filename);
                continue;
            }

            newfilename = malloc(strlen(data_dir) + 1 + strlen(prefix) - strlen(root) + strlen(dent->d_name) + 1);
            strcpy(newfilename, data_dir);
            strcat(newfilename, "/");
            strcat(newfilename, prefix + strlen(root) + 1);

            if (!mkdir_p(newfilename)) {
                free(filename);
                free(newfilename);
                continue;
            }

            strcat(newfilename, "/");
            strcat(newfilename, dent->d_name);

            if (stat(newfilename, &st) == 0 &&
                (gzipped || st.st_size == (long long) size)) {
                free(filename);
                free(newfilename);
                continue;
            }

            f = fopen(newfilename, "w");
            if (f == NULL) {
                LOGE("extract_files: Could not open %s for writing: %s", newfilename, strerror(errno));
                free(filename);
                free(newfilename);
                continue;
            }

            if (!gzipped) {
                if (fwrite(apkentry, size, 1, f) != 1) {
                    LOGE("extract_files: Could not write %lld bytes to %s: %s", (long long) size, newfilename, strerror(errno));
                } else {
                    LOGI("extract_files: Copied %s to %s: %lld bytes", filename, newfilename, (long long) size);
                }
            } else {
                size = extract_gzipped(filename, apkentry, size, f);
                LOGI("extract_files: Decompressed %s to %s: %lld bytes", filename, newfilename, (long long) size);
            }

            fclose(f);

            free(filename);
            free(newfilename);
        }
    }
    lo_apk_closedir(tree);
}

/* Android's JNI works only to libraries loaded through Java's
 * System.loadLibrary(), it seems. But now with just one big app-specific .so
 * on Android, that would not be a problem, but for historical reasons, we
 * have JNI wrappers here, and then call the VCL etc function from them. Oh
 * well, one could say it's clean to have all the Android-specific JNI
 * functions here in this file.
 */

extern void osl_setCommandArgs(int, char **);

__attribute__ ((visibility("default")))
void
Java_org_libreoffice_android_Bootstrap_setCommandArgs(JNIEnv* env,
                                                      jobject clazz,
                                                      jobject argv)
{
    char **c_argv;
    int c_argc;
    Dl_info lo_bootstrap_info;

    (void) clazz;

    if (!get_jni_string_array(env, "setCommandArgs :argv", argv, &c_argc, (const char ***) &c_argv))
        return;

    if (dladdr(Java_org_libreoffice_android_Bootstrap_setCommandArgs, &lo_bootstrap_info) != 0) {
        char *new_argv0 = malloc(strlen(lo_bootstrap_info.dli_fname) + strlen(c_argv[0]));
        char *slash;
        strcpy(new_argv0, lo_bootstrap_info.dli_fname);
        slash = strrchr(new_argv0, '/');
        if (slash != NULL)
            *slash = '\0';
        slash = strrchr(new_argv0, '/');
        if (slash != NULL)
            strcpy(slash+1, c_argv[0]);
        else
            strcpy(new_argv0, c_argv[0]);
        free(c_argv[0]);
        c_argv[0] = new_argv0;
    }

    osl_setCommandArgs(c_argc, c_argv);
}

/* Code for reading lines from the pipe based on the (Apache-licensed) Android
 * logwrapper.c
 */

static int
read_from(int fd, const char *tag, char *buffer, int *sz, int *a, int *b, size_t sizeof_buffer)
{
    int nread;

    nread = read(fd, buffer+*b, sizeof_buffer - 1 - *b);
    *sz = nread;

    if (nread == -1) {
        LOGE("redirect_thread: Reading from %d failed: %s", fd, strerror(errno));
        close(fd);
        return -1;
    }

    if (nread == 0) {
        LOGI("redirect_thread: EOF from fd %d", fd);
        close(fd);
        return 0;
    }

    *sz += *b;

    for (*b = 0; *b < *sz; (*b)++) {
        if (buffer[*b] == '\n') {
            buffer[*b] = '\0';
            __android_log_print(ANDROID_LOG_INFO, tag, "%s", &buffer[*a]);
            *a = *b + 1;
        }
    }

    if (*a == 0 && *b == (int) sizeof_buffer - 1) {
        // buffer is full, flush
        buffer[*b] = '\0';
        __android_log_print(ANDROID_LOG_INFO, tag, "%s", &buffer[*a]);
        *b = 0;
    } else if (*a != *b) {
        // Keep left-overs
        *b -= *a;
        memmove(buffer, &buffer[*a], *b);
        *a = 0;
    } else {
        *a = 0;
        *b = 0;
    }

    return nread;
}

static int stdout_pipe[2], stderr_pipe[2];

static void *
redirect_thread(void *arg)
{
    char buffer[2][4096];
    int a[2] = { 0, 0 };
    int b[2] = { 0, 0 };
    int sz[2];

    (void) arg;

    while (1) {
        fd_set readfds;
        int nfds = 0;

        FD_ZERO(&readfds);
        if (stdout_pipe[0] != -1) {
            FD_SET(stdout_pipe[0], &readfds);
            nfds = MAX(nfds, stdout_pipe[0] + 1);
        }
        if (stderr_pipe[0] != -1) {
            FD_SET(stderr_pipe[0], &readfds);
            nfds = MAX(nfds, stderr_pipe[0] + 1);
        }
        if (nfds == 0) {
            LOGI("redirect_thread: Nothing to read any more, thread exiting");
            return NULL;
        }

        if (select(nfds, &readfds, NULL, NULL, NULL) == -1) {
            LOGE("redirect_thread: select failed: %s, thread exiting", strerror(errno));
            close(stdout_pipe[0]);
            stdout_pipe[0] = -1;
            close(stderr_pipe[0]);
            stderr_pipe[0] = -1;
            return NULL;
        }

        if (stdout_pipe[0] != -1 &&
            FD_ISSET(stdout_pipe[0], &readfds)) {
            if (read_from(stdout_pipe[0], "stdout", buffer[0], &sz[0], &a[0], &b[0], sizeof(buffer[0])) <= 0) {
                stdout_pipe[0] = -1;
            }
        }

        if (stderr_pipe[0] != -1 &&
            FD_ISSET(stderr_pipe[0], &readfds)) {
            if (read_from(stderr_pipe[0], "stderr", buffer[1], &sz[1], &a[1], &b[1], sizeof(buffer[1])) <= 0) {
                stderr_pipe[0] = -1;
            }
        }
    }
}

static int
redirect_to_null(void)
{
    int null = open("/dev/null", O_WRONLY);
    if (null == -1) {
        LOGE("redirect_stdio: Could not open /dev/null: %s", strerror(errno));
        /* If we can't redirect stdout or stderr to /dev/null, just close them
         * then instead. Huh?
         */
        close(1);
        close(2);
        return 0;
    }
    if (dup2(null, 1) == -1) {
        LOGE("redirect_stdio: Could not dup2 %d to 1: %s", null, strerror(errno));
        close(null);
        close(1);
        close(2);
        return 0;
    }
    if (dup2(null, 2) == -1) {
        LOGE("redirect_stdio: Could not dup2 %d to 2: %s", null, strerror(errno));
        close(null);
        close(1);
        close(2);
        return 0;
    }
    close(null);
    return 1;
}

__attribute__ ((visibility("default")))
void
Java_org_libreoffice_android_Bootstrap_redirect_1stdio(JNIEnv* env,
                                                       jobject clazz,
                                                       jboolean state)
{
    static jboolean current = JNI_FALSE;
    pthread_t thread;
    pthread_attr_t attr;

    (void) env;
    (void) clazz;

    if (state == current)
        return;

    if (state == JNI_FALSE) {
        if (!redirect_to_null())
            return;
    } else {
        if (pipe(stdout_pipe) == -1) {
            LOGE("redirect_stdio: Could not create pipes: %s", strerror(errno));
            return;
        }
        if (pipe(stderr_pipe) == -1) {
            LOGE("redirect_stdio: Could not create pipes: %s", strerror(errno));
            close(stdout_pipe[0]);
            close(stdout_pipe[1]);
            return;
        }
        LOGI("redirect_stdio: stdout pipe: [%d,%d], stderr pipe: [%d,%d]",
             stdout_pipe[0], stdout_pipe[1], stderr_pipe[0], stderr_pipe[1]);

        if (dup2(stdout_pipe[1], 1) == -1) {
            LOGE("redirect_stdio: Could not dup2 %d to 1: %s", stdout_pipe[1], strerror(errno));
            close(stdout_pipe[0]);
            close(stdout_pipe[1]);
            close(stderr_pipe[0]);
            close(stderr_pipe[1]);
            return;
        }

        if (dup2(stderr_pipe[1], 2) == -1) {
            LOGE("redirect_stdio: Could not dup2 %d to 2: %s", stdout_pipe[1], strerror(errno));
            /* stdout has already been redirected to its pipe, so redirect
             * it back to /dev/null
             */
            redirect_to_null();
            close(stdout_pipe[0]);
            close(stdout_pipe[1]);
            close(stderr_pipe[0]);
            close(stderr_pipe[1]);
            return;
        }
        close(stdout_pipe[1]);
        close(stderr_pipe[1]);

        if (pthread_attr_init(&attr) != 0 ||
            pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED) != 0 ||
            pthread_create(&thread, &attr, redirect_thread, NULL) != 0) {
            LOGE("redirect_stdio: Could not create thread: %s", strerror(errno));
            redirect_to_null();
            close(stdout_pipe[0]);
            close(stderr_pipe[0]);
            return;
        }
    }
    current = state;
    return;
}

__attribute__ ((visibility("default")))
jlong
Java_org_libreoffice_android_Bootstrap_address_1of_1direct_1byte_1buffer(JNIEnv *env,
                                                                         jobject bbuffer)
{
    return (jlong) (intptr_t) (*env)->GetDirectBufferAddress(env, bbuffer);
}

__attribute__ ((visibility("default")))
JavaVM *
lo_get_javavm(void)
{
    return the_java_vm;
}

__attribute__ ((visibility("default")))
const char *
lo_get_app_data_dir(void)
{
    return data_dir;
}

/* vim:set shiftwidth=4 softtabstop=4 expandtab: */