/*
 * Copyright 1998-2006 Sun Microsystems, Inc.  All Rights Reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun in the LICENSE file that accompanied this code.
 *
 * This code 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
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

#include <assert.h>
#include <sys/types.h>
#include <sys/time.h>
#include <sys/stat.h>
#include <sys/statvfs.h>
#include <string.h>
#include <stdlib.h>
#include <dlfcn.h>
#include <limits.h>

#include "jni.h"
#include "jni_util.h"
#include "jlong.h"
#include "jvm.h"
#include "io_util.h"
#include "java_io_FileSystem.h"
#include "java_io_UnixFileSystem.h"


/* -- Field IDs -- */

static struct {
    jfieldID path;
} ids;


JNIEXPORT void JNICALL
Java_java_io_UnixFileSystem_initIDs(JNIEnv *env, jclass cls)
{
    jclass fileClass = (*env)->FindClass(env, "java/io/File");
    if (!fileClass) return;
    ids.path = (*env)->GetFieldID(env, fileClass,
                                  "path", "Ljava/lang/String;");
}


/* -- Large-file support -- */

/* LINUX_FIXME: ifdef __solaris__ here is wrong.  We need to move the
 * definition of stat64 into a solaris_largefile.h and create a
 * linux_largefile.h with a good stat64 structure to compile on
 * glibc2.0 based systems.
 */
#if defined(__solaris__) && !defined(_LFS_LARGEFILE) || !_LFS_LARGEFILE

/* The stat64 structure must be provided for systems without large-file support
   (e.g., Solaris 2.5.1).  These definitions are copied from the Solaris 2.6
   <sys/stat.h> and <sys/types.h> files.
 */

typedef longlong_t      off64_t;        /* offsets within files */
typedef u_longlong_t    ino64_t;        /* expanded inode type  */
typedef longlong_t      blkcnt64_t;     /* count of file blocks */

struct  stat64 {
        dev_t   st_dev;
        long    st_pad1[3];
        ino64_t st_ino;
        mode_t  st_mode;
        nlink_t st_nlink;
        uid_t   st_uid;
        gid_t   st_gid;
        dev_t   st_rdev;
        long    st_pad2[2];
        off64_t st_size;
        timestruc_t st_atim;
        timestruc_t st_mtim;
        timestruc_t st_ctim;
        long    st_blksize;
        blkcnt64_t st_blocks;
        char    st_fstype[_ST_FSTYPSZ];
        long    st_pad4[8];
};

#endif  /* !_LFS_LARGEFILE */

typedef int (*STAT64)(const char *, struct stat64 *);

#if defined(__linux__) && defined(_LARGEFILE64_SOURCE)
static STAT64 stat64_ptr = &stat64;
#else
static STAT64 stat64_ptr = NULL;
#endif

#ifndef __linux__
#ifdef __GNUC__
static void init64IO(void) __attribute__((constructor));
#else
#pragma init(init64IO)
#endif
#endif

static void init64IO(void) {
    void *handle = dlopen(0, RTLD_LAZY);
    stat64_ptr = (STAT64) dlsym(handle, "_stat64");
    dlclose(handle);
}


/* -- Path operations -- */

extern int canonicalize(char *path, const char *out, int len);

JNIEXPORT jstring JNICALL
Java_java_io_UnixFileSystem_canonicalize0(JNIEnv *env, jobject this,
                                          jstring pathname)
{
    jstring rv = NULL;

    WITH_PLATFORM_STRING(env, pathname, path) {
        char canonicalPath[JVM_MAXPATHLEN];
        if (canonicalize(JVM_NativePath((char *)path),
                         canonicalPath, JVM_MAXPATHLEN) < 0) {
            JNU_ThrowIOExceptionWithLastError(env, "Bad pathname");
        } else {
            rv = JNU_NewStringPlatform(env, canonicalPath);
        }
    } END_PLATFORM_STRING(env, path);
    return rv;
}


/* -- Attribute accessors -- */


static jboolean
statMode(const char *path, int *mode)
{
    if (stat64_ptr) {
        struct stat64 sb;
        if (((*stat64_ptr)(path, &sb)) == 0) {
            *mode = sb.st_mode;
            return JNI_TRUE;
        }
    } else {
        struct stat sb;
        if (stat(path, &sb) == 0) {
            *mode = sb.st_mode;
            return JNI_TRUE;
        }
    }
    return JNI_FALSE;
}


JNIEXPORT jint JNICALL
Java_java_io_UnixFileSystem_getBooleanAttributes0(JNIEnv *env, jobject this,
                                                  jobject file)
{
    jint rv = 0;

    WITH_FIELD_PLATFORM_STRING(env, file, ids.path, path) {
        int mode;
        if (statMode(path, &mode)) {
            int fmt = mode & S_IFMT;
            rv = (jint) (java_io_FileSystem_BA_EXISTS
                  | ((fmt == S_IFREG) ? java_io_FileSystem_BA_REGULAR : 0)
                  | ((fmt == S_IFDIR) ? java_io_FileSystem_BA_DIRECTORY : 0));
        }
    } END_PLATFORM_STRING(env, path);
    return rv;
}

JNIEXPORT jboolean JNICALL
Java_java_io_UnixFileSystem_checkAccess(JNIEnv *env, jobject this,
                                        jobject file, jint a)
{
    jboolean rv = JNI_FALSE;
    int mode;
    switch (a) {
    case java_io_FileSystem_ACCESS_READ:
        mode = R_OK;
        break;
    case java_io_FileSystem_ACCESS_WRITE:
        mode = W_OK;
        break;
    case java_io_FileSystem_ACCESS_EXECUTE:
        mode = X_OK;
        break;
    default: assert(0);
    }
    WITH_FIELD_PLATFORM_STRING(env, file, ids.path, path) {
        if (access(path, mode) == 0) {
            rv = JNI_TRUE;
        }
    } END_PLATFORM_STRING(env, path);
    return rv;
}


JNIEXPORT jboolean JNICALL
Java_java_io_UnixFileSystem_setPermission(JNIEnv *env, jobject this,
                                          jobject file,
                                          jint access,
                                          jboolean enable,
                                          jboolean owneronly)
{
    jboolean rv = JNI_FALSE;

    WITH_FIELD_PLATFORM_STRING(env, file, ids.path, path) {
        int amode, mode;
        switch (access) {
        case java_io_FileSystem_ACCESS_READ:
            if (owneronly)
                amode = S_IRUSR;
            else
                amode = S_IRUSR | S_IRGRP | S_IROTH;
            break;
        case java_io_FileSystem_ACCESS_WRITE:
            if (owneronly)
                amode = S_IWUSR;
            else
                amode = S_IWUSR | S_IWGRP | S_IWOTH;
            break;
        case java_io_FileSystem_ACCESS_EXECUTE:
            if (owneronly)
                amode = S_IXUSR;
            else
                amode = S_IXUSR | S_IXGRP | S_IXOTH;
            break;
        default:
            assert(0);
        }
        if (statMode(path, &mode)) {
            if (enable)
                mode |= amode;
            else
                mode &= ~amode;
            if (chmod(path, mode) >= 0) {
                rv = JNI_TRUE;
            }
        }
    } END_PLATFORM_STRING(env, path);
    return rv;
}

JNIEXPORT jlong JNICALL
Java_java_io_UnixFileSystem_getLastModifiedTime(JNIEnv *env, jobject this,
                                                jobject file)
{
    jlong rv = 0;

    WITH_FIELD_PLATFORM_STRING(env, file, ids.path, path) {
        if (stat64_ptr) {
            struct stat64 sb;
            if (((*stat64_ptr)(path, &sb)) == 0) {
                rv = 1000 * (jlong)sb.st_mtime;
            }
        } else {
            struct stat sb;
            if (stat(path, &sb) == 0) {
                rv = 1000 * (jlong)sb.st_mtime;
            }
        }
    } END_PLATFORM_STRING(env, path);
    return rv;
}


JNIEXPORT jlong JNICALL
Java_java_io_UnixFileSystem_getLength(JNIEnv *env, jobject this,
                                      jobject file)
{
    jlong rv = 0;

    WITH_FIELD_PLATFORM_STRING(env, file, ids.path, path) {
        if (stat64_ptr) {
            struct stat64 sb;
            if (((*stat64_ptr)(path, &sb)) == 0) {
                rv = sb.st_size;
            }
        } else {
            struct stat sb;
            if (stat(path, &sb) == 0) {
                rv = sb.st_size;
            }
        }
    } END_PLATFORM_STRING(env, path);
    return rv;
}


/* -- File operations -- */


JNIEXPORT jboolean JNICALL
Java_java_io_UnixFileSystem_createFileExclusively(JNIEnv *env, jclass cls,
                                                  jstring pathname)
{
    jboolean rv = JNI_FALSE;

    WITH_PLATFORM_STRING(env, pathname, path) {
        int fd;
        if (!strcmp (path, "/")) {
            fd = JVM_EEXIST;    /* The root directory always exists */
        } else {
            fd = JVM_Open(path, JVM_O_RDWR | JVM_O_CREAT | JVM_O_EXCL, 0666);
        }
        if (fd < 0) {
            if (fd != JVM_EEXIST) {
                JNU_ThrowIOExceptionWithLastError(env, path);
            }
        } else {
            JVM_Close(fd);
            rv = JNI_TRUE;
        }
    } END_PLATFORM_STRING(env, path);
    return rv;
}


JNIEXPORT jboolean JNICALL
Java_java_io_UnixFileSystem_delete0(JNIEnv *env, jobject this,
                                    jobject file)
{
    jboolean rv = JNI_FALSE;

    WITH_FIELD_PLATFORM_STRING(env, file, ids.path, path) {
        if (remove(path) == 0) {
            rv = JNI_TRUE;
        }
    } END_PLATFORM_STRING(env, path);
    return rv;
}


JNIEXPORT jobjectArray JNICALL
Java_java_io_UnixFileSystem_list(JNIEnv *env, jobject this,
                                 jobject file)
{
    DIR *dir = NULL;
    struct dirent64 *ptr;
    struct dirent64 *result;
    int len, maxlen;
    jobjectArray rv, old;

    WITH_FIELD_PLATFORM_STRING(env, file, ids.path, path) {
        dir = opendir(path);
    } END_PLATFORM_STRING(env, path);
    if (dir == NULL) return NULL;

    ptr = malloc(sizeof(struct dirent64) + (PATH_MAX + 1));
    if (ptr == NULL) {
        JNU_ThrowOutOfMemoryError(env, "heap allocation failed");
        closedir(dir);
        return NULL;
    }

    /* Allocate an initial String array */
    len = 0;
    maxlen = 16;
    rv = (*env)->NewObjectArray(env, maxlen, JNU_ClassString(env), NULL);
    if (rv == NULL) goto error;

    /* Scan the directory */
    while ((readdir64_r(dir, ptr, &result) == 0)  && (result != NULL)) {
        jstring name;
        if (!strcmp(ptr->d_name, ".") || !strcmp(ptr->d_name, ".."))
            continue;
        if (len == maxlen) {
            old = rv;
            rv = (*env)->NewObjectArray(env, maxlen <<= 1,
                                        JNU_ClassString(env), NULL);
            if (rv == NULL) goto error;
            if (JNU_CopyObjectArray(env, rv, old, len) < 0) goto error;
            (*env)->DeleteLocalRef(env, old);
        }
        name = JNU_NewStringPlatform(env, ptr->d_name);
        if (name == NULL) goto error;
        (*env)->SetObjectArrayElement(env, rv, len++, name);
        (*env)->DeleteLocalRef(env, name);
    }
    closedir(dir);
    free(ptr);

    /* Copy the final results into an appropriately-sized array */
    old = rv;
    rv = (*env)->NewObjectArray(env, len, JNU_ClassString(env), NULL);
    if (rv == NULL) {
        return NULL;
    }
    if (JNU_CopyObjectArray(env, rv, old, len) < 0) {
        return NULL;
    }
    return rv;

 error:
    closedir(dir);
    free(ptr);
    return NULL;
}


JNIEXPORT jboolean JNICALL
Java_java_io_UnixFileSystem_createDirectory(JNIEnv *env, jobject this,
                                            jobject file)
{
    jboolean rv = JNI_FALSE;

    WITH_FIELD_PLATFORM_STRING(env, file, ids.path, path) {
        if (mkdir(path, 0777) == 0) {
            rv = JNI_TRUE;
        }
    } END_PLATFORM_STRING(env, path);
    return rv;
}


JNIEXPORT jboolean JNICALL
Java_java_io_UnixFileSystem_rename0(JNIEnv *env, jobject this,
                                    jobject from, jobject to)
{
    jboolean rv = JNI_FALSE;

    WITH_FIELD_PLATFORM_STRING(env, from, ids.path, fromPath) {
        WITH_FIELD_PLATFORM_STRING(env, to, ids.path, toPath) {
            if (rename(fromPath, toPath) == 0) {
                rv = JNI_TRUE;
            }
        } END_PLATFORM_STRING(env, toPath);
    } END_PLATFORM_STRING(env, fromPath);
    return rv;
}


/* Bug in solaris /usr/include/sys/time.h? */
#ifdef __solaris__
extern int utimes(const char *, const struct timeval *);
#elif defined(__linux___)
extern int utimes(const char *, struct timeval *);
#endif


JNIEXPORT jboolean JNICALL
Java_java_io_UnixFileSystem_setLastModifiedTime(JNIEnv *env, jobject this,
                                                jobject file, jlong time)
{
    jboolean rv = JNI_FALSE;

    WITH_FIELD_PLATFORM_STRING(env, file, ids.path, path) {
        struct timeval tv[2];
#ifdef __solaris__
        timestruc_t ts;

        if (stat64_ptr) {
            struct stat64 sb;
            if (((*stat64_ptr)(path, &sb)) == 0)
                ts = sb.st_atim;
            else
                goto error;
        } else {
            struct stat sb;
            if (stat(path, &sb) == 0)
                ts = sb.st_atim;
            else
                goto error;
        }
#endif

        /* Preserve access time */
#ifdef __linux__
        struct stat sb;

        if (stat(path, &sb) == 0) {

        tv[0].tv_sec = sb.st_atime;
        tv[0].tv_usec = 0;
        }
#else
        tv[0].tv_sec = ts.tv_sec;
        tv[0].tv_usec = ts.tv_nsec / 1000;
#endif

        /* Change last-modified time */
        tv[1].tv_sec = time / 1000;
        tv[1].tv_usec = (time % 1000) * 1000;

        if (utimes(path, tv) >= 0)
            rv = JNI_TRUE;

    error: ;
    } END_PLATFORM_STRING(env, path);

    return rv;
}


JNIEXPORT jboolean JNICALL
Java_java_io_UnixFileSystem_setReadOnly(JNIEnv *env, jobject this,
                                        jobject file)
{
    jboolean rv = JNI_FALSE;

    WITH_FIELD_PLATFORM_STRING(env, file, ids.path, path) {
        int mode;
        if (statMode(path, &mode)) {
            if (chmod(path, mode & ~(S_IWUSR | S_IWGRP | S_IWOTH)) >= 0) {
                rv = JNI_TRUE;
            }
        }
    } END_PLATFORM_STRING(env, path);
    return rv;
}

JNIEXPORT jlong JNICALL
Java_java_io_UnixFileSystem_getSpace(JNIEnv *env, jobject this,
                                     jobject file, jint t)
{
    jlong rv = 0L;

    WITH_FIELD_PLATFORM_STRING(env, file, ids.path, path) {
        struct statvfs fsstat;
        memset(&fsstat, 0, sizeof(struct statvfs));
        if (statvfs(path, &fsstat) == 0) {
            switch(t) {
            case java_io_FileSystem_SPACE_TOTAL:
                rv = jlong_mul(long_to_jlong(fsstat.f_frsize),
                               long_to_jlong(fsstat.f_blocks));
                break;
            case java_io_FileSystem_SPACE_FREE:
                rv = jlong_mul(long_to_jlong(fsstat.f_frsize),
                               long_to_jlong(fsstat.f_bfree));
                break;
            case java_io_FileSystem_SPACE_USABLE:
                rv = jlong_mul(long_to_jlong(fsstat.f_frsize),
                               long_to_jlong(fsstat.f_bavail));
                break;
            default:
                assert(0);
            }
        }
    } END_PLATFORM_STRING(env, path);
    return rv;
}