/* 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/. */

/*
** uxshm.c -- Unix Implementations NSPR Named Shared Memory
**
**
** lth. Jul-1999.
**
*/
#include <string.h>
#include <prshm.h>
#include <prerr.h>
#include <prmem.h>
#include "primpl.h"
#include <fcntl.h>

extern PRLogModuleInfo* _pr_shm_lm;

#define NSPR_IPC_SHM_KEY 'b'
/*
** Implementation for System V
*/
#if defined PR_HAVE_SYSV_NAMED_SHARED_MEMORY
#include <sys/ipc.h>
#include <sys/shm.h>
#include <sys/types.h>
#include <sys/stat.h>

#define _MD_OPEN_SHARED_MEMORY _MD_OpenSharedMemory
#define _MD_ATTACH_SHARED_MEMORY _MD_AttachSharedMemory
#define _MD_DETACH_SHARED_MEMORY _MD_DetachSharedMemory
#define _MD_CLOSE_SHARED_MEMORY _MD_CloseSharedMemory
#define _MD_DELETE_SHARED_MEMORY _MD_DeleteSharedMemory

extern PRSharedMemory*
_MD_OpenSharedMemory(const char* name, PRSize size,
                     PRIntn flags, PRIntn mode)
{
    PRStatus rc = PR_SUCCESS;
    key_t key;
    PRSharedMemory* shm;
    char ipcname[PR_IPC_NAME_SIZE];

    rc = _PR_MakeNativeIPCName(name, ipcname, PR_IPC_NAME_SIZE, _PRIPCShm);
    if (PR_FAILURE == rc) {
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(
            _pr_shm_lm, PR_LOG_DEBUG,
            ("_MD_OpenSharedMemory(): _PR_MakeNativeIPCName() failed: %s", name));
        return (NULL);
    }

    shm = PR_NEWZAP(PRSharedMemory);
    if (NULL == shm) {
        PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("PR_OpenSharedMemory: New PRSharedMemory out of memory"));
        return (NULL);
    }

    shm->ipcname = (char*)PR_MALLOC(strlen(ipcname) + 1);
    if (NULL == shm->ipcname) {
        PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("PR_OpenSharedMemory: New shm->ipcname out of memory"));
        PR_DELETE(shm);
        return (NULL);
    }

    /* copy args to struct */
    strcpy(shm->ipcname, ipcname);
    shm->size = size;
    shm->mode = mode;
    shm->flags = flags;
    shm->ident = _PR_SHM_IDENT;

    /* create the file first */
    if (flags & PR_SHM_CREATE) {
        int osfd = open(shm->ipcname, (O_RDWR | O_CREAT), shm->mode);
        if (-1 == osfd) {
            _PR_MD_MAP_OPEN_ERROR(errno);
            PR_FREEIF(shm->ipcname);
            PR_DELETE(shm);
            return (NULL);
        }
        if (close(osfd) == -1) {
            _PR_MD_MAP_CLOSE_ERROR(errno);
            PR_FREEIF(shm->ipcname);
            PR_DELETE(shm);
            return (NULL);
        }
    }

    /* hash the shm.name to an ID */
    key = ftok(shm->ipcname, NSPR_IPC_SHM_KEY);
    if (-1 == key) {
        rc = PR_FAILURE;
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_OpenSharedMemory(): ftok() failed on name: %s", shm->ipcname));
        PR_FREEIF(shm->ipcname);
        PR_DELETE(shm);
        return (NULL);
    }

    /* get the shared memory */
    if (flags & PR_SHM_CREATE) {
        shm->id = shmget(key, shm->size, (shm->mode | IPC_CREAT | IPC_EXCL));
        if (shm->id >= 0) {
            return (shm);
        }
        if ((errno == EEXIST) && (flags & PR_SHM_EXCL)) {
            PR_SetError(PR_FILE_EXISTS_ERROR, errno);
            PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
                   ("_MD_OpenSharedMemory(): shmget() exclusive failed, errno: %d",
                    errno));
            PR_FREEIF(shm->ipcname);
            PR_DELETE(shm);
            return (NULL);
        }
    }

    shm->id = shmget(key, shm->size, shm->mode);
    if (-1 == shm->id) {
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_OpenSharedMemory(): shmget() failed, errno: %d", errno));
        PR_FREEIF(shm->ipcname);
        PR_DELETE(shm);
        return (NULL);
    }

    return (shm);
} /* end _MD_OpenSharedMemory() */

extern void*
_MD_AttachSharedMemory(PRSharedMemory* shm, PRIntn flags)
{
    void* addr;
    PRUint32 aFlags = shm->mode;

    PR_ASSERT(shm->ident == _PR_SHM_IDENT);

    aFlags |= (flags & PR_SHM_READONLY) ? SHM_RDONLY : 0;

    addr = shmat(shm->id, NULL, aFlags);
    if ((void*)-1 == addr) {
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_AttachSharedMemory(): shmat() failed on name: %s, OsError: %d",
                shm->ipcname, PR_GetOSError()));
        addr = NULL;
    }

    return addr;
}

extern PRStatus
_MD_DetachSharedMemory(PRSharedMemory* shm, void* addr)
{
    PRStatus rc = PR_SUCCESS;
    PRIntn urc;

    PR_ASSERT(shm->ident == _PR_SHM_IDENT);

    urc = shmdt(addr);
    if (-1 == urc) {
        rc = PR_FAILURE;
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(
            _pr_shm_lm, PR_LOG_DEBUG,
            ("_MD_DetachSharedMemory(): shmdt() failed on name: %s", shm->ipcname));
    }

    return rc;
}

extern PRStatus
_MD_CloseSharedMemory(PRSharedMemory* shm)
{
    PR_ASSERT(shm->ident == _PR_SHM_IDENT);

    PR_FREEIF(shm->ipcname);
    PR_DELETE(shm);

    return PR_SUCCESS;
}

extern PRStatus
_MD_DeleteSharedMemory(const char* name)
{
    PRStatus rc = PR_SUCCESS;
    key_t key;
    int id;
    PRIntn urc;
    char ipcname[PR_IPC_NAME_SIZE];

    rc = _PR_MakeNativeIPCName(name, ipcname, PR_IPC_NAME_SIZE, _PRIPCShm);
    if (PR_FAILURE == rc) {
        PR_SetError(PR_UNKNOWN_ERROR, errno);
        PR_LOG(
            _pr_shm_lm, PR_LOG_DEBUG,
            ("_MD_DeleteSharedMemory(): _PR_MakeNativeIPCName() failed: %s", name));
        return (PR_FAILURE);
    }

    /* create the file first */
    {
        int osfd = open(ipcname, (O_RDWR | O_CREAT), 0666);
        if (-1 == osfd) {
            _PR_MD_MAP_OPEN_ERROR(errno);
            return (PR_FAILURE);
        }
        if (close(osfd) == -1) {
            _PR_MD_MAP_CLOSE_ERROR(errno);
            return (PR_FAILURE);
        }
    }

    /* hash the shm.name to an ID */
    key = ftok(ipcname, NSPR_IPC_SHM_KEY);
    if (-1 == key) {
        rc = PR_FAILURE;
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_DeleteSharedMemory(): ftok() failed on name: %s", ipcname));
    }

    id = shmget(key, 0, 0);
    if (-1 == id) {
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_DeleteSharedMemory(): shmget() failed, errno: %d", errno));
        return (PR_FAILURE);
    }

    urc = shmctl(id, IPC_RMID, NULL);
    if (-1 == urc) {
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_DeleteSharedMemory(): shmctl() failed on name: %s", ipcname));
        return (PR_FAILURE);
    }

    urc = unlink(ipcname);
    if (-1 == urc) {
        _PR_MD_MAP_UNLINK_ERROR(errno);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_DeleteSharedMemory(): unlink() failed: %s", ipcname));
        return (PR_FAILURE);
    }

    return rc;
} /* end _MD_DeleteSharedMemory() */

/*
** Implementation for Posix
*/
#elif defined PR_HAVE_POSIX_NAMED_SHARED_MEMORY
#include <sys/mman.h>

#define _MD_OPEN_SHARED_MEMORY _MD_OpenSharedMemory
#define _MD_ATTACH_SHARED_MEMORY _MD_AttachSharedMemory
#define _MD_DETACH_SHARED_MEMORY _MD_DetachSharedMemory
#define _MD_CLOSE_SHARED_MEMORY _MD_CloseSharedMemory
#define _MD_DELETE_SHARED_MEMORY _MD_DeleteSharedMemory

struct _MDSharedMemory {
    int handle;
};

extern PRSharedMemory*
_MD_OpenSharedMemory(const char* name, PRSize size,
                     PRIntn flags, PRIntn mode)
{
    PRStatus rc = PR_SUCCESS;
    PRInt32 end;
    PRSharedMemory* shm;
    char ipcname[PR_IPC_NAME_SIZE];

    rc = _PR_MakeNativeIPCName(name, ipcname, PR_IPC_NAME_SIZE, _PRIPCShm);
    if (PR_FAILURE == rc) {
        PR_SetError(PR_UNKNOWN_ERROR, errno);
        PR_LOG(
            _pr_shm_lm, PR_LOG_DEBUG,
            ("_MD_OpenSharedMemory(): _PR_MakeNativeIPCName() failed: %s", name));
        return (NULL);
    }

    shm = PR_NEWZAP(PRSharedMemory);
    if (NULL == shm) {
        PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("PR_OpenSharedMemory: New PRSharedMemory out of memory"));
        return (NULL);
    }

    shm->ipcname = PR_MALLOC(strlen(ipcname) + 1);
    if (NULL == shm->ipcname) {
        PR_SetError(PR_OUT_OF_MEMORY_ERROR, 0);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("PR_OpenSharedMemory: New shm->ipcname out of memory"));
        return (NULL);
    }

    /* copy args to struct */
    strcpy(shm->ipcname, ipcname);
    shm->size = size;
    shm->mode = mode;
    shm->flags = flags;
    shm->ident = _PR_SHM_IDENT;

    /*
    ** Create the shared memory
    */
    if (flags & PR_SHM_CREATE) {
        int oflag = (O_CREAT | O_RDWR);

        if (flags & PR_SHM_EXCL) {
            oflag |= O_EXCL;
        }
        shm->id = shm_open(shm->ipcname, oflag, shm->mode);
    } else {
        shm->id = shm_open(shm->ipcname, O_RDWR, shm->mode);
    }

    if (-1 == shm->id) {
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_OpenSharedMemory(): shm_open failed: %s, OSError: %d",
                shm->ipcname, PR_GetOSError()));
        PR_DELETE(shm->ipcname);
        PR_DELETE(shm);
        return (NULL);
    }

    end = ftruncate(shm->id, shm->size);
    if (-1 == end) {
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_OpenSharedMemory(): ftruncate failed, OSError: %d",
                PR_GetOSError()));
        PR_DELETE(shm->ipcname);
        PR_DELETE(shm);
        return (NULL);
    }

    return (shm);
} /* end _MD_OpenSharedMemory() */

extern void*
_MD_AttachSharedMemory(PRSharedMemory* shm, PRIntn flags)
{
    void* addr;
    PRIntn prot = (PROT_READ | PROT_WRITE);

    PR_ASSERT(shm->ident == _PR_SHM_IDENT);

    if (PR_SHM_READONLY == flags) {
        prot ^= PROT_WRITE;
    }

    addr = mmap((void*)0, shm->size, prot, MAP_SHARED, shm->id, 0);
    if ((void*)-1 == addr) {
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_AttachSharedMemory(): mmap failed: %s, errno: %d",
                shm->ipcname, PR_GetOSError()));
        addr = NULL;
    } else {
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_AttachSharedMemory(): name: %s, attached at: %p", shm->ipcname,
                addr));
    }

    return addr;
}

extern PRStatus
_MD_DetachSharedMemory(PRSharedMemory* shm, void* addr)
{
    PRStatus rc = PR_SUCCESS;
    PRIntn urc;

    PR_ASSERT(shm->ident == _PR_SHM_IDENT);

    urc = munmap(addr, shm->size);
    if (-1 == urc) {
        rc = PR_FAILURE;
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_DetachSharedMemory(): munmap failed: %s, errno: %d",
                shm->ipcname, PR_GetOSError()));
    }
    return rc;
}

extern PRStatus
_MD_CloseSharedMemory(PRSharedMemory* shm)
{
    int urc;

    PR_ASSERT(shm->ident == _PR_SHM_IDENT);

    urc = close(shm->id);
    if (-1 == urc) {
        _PR_MD_MAP_CLOSE_ERROR(errno);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_CloseSharedMemory(): close() failed, error: %d",
                PR_GetOSError()));
        return (PR_FAILURE);
    }
    PR_DELETE(shm->ipcname);
    PR_DELETE(shm);
    return PR_SUCCESS;
}

extern PRStatus
_MD_DeleteSharedMemory(const char* name)
{
    PRStatus rc = PR_SUCCESS;
    PRUintn urc;
    char ipcname[PR_IPC_NAME_SIZE];

    rc = _PR_MakeNativeIPCName(name, ipcname, PR_IPC_NAME_SIZE, _PRIPCShm);
    if (PR_FAILURE == rc) {
        PR_SetError(PR_UNKNOWN_ERROR, errno);
        PR_LOG(
            _pr_shm_lm, PR_LOG_DEBUG,
            ("_MD_OpenSharedMemory(): _PR_MakeNativeIPCName() failed: %s", name));
        return rc;
    }

    urc = shm_unlink(ipcname);
    if (-1 == urc) {
        rc = PR_FAILURE;
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_DeleteSharedMemory(): shm_unlink failed: %s, errno: %d",
                ipcname, PR_GetOSError()));
    } else {
        PR_LOG(_pr_shm_lm, PR_LOG_DEBUG,
               ("_MD_DeleteSharedMemory(): %s, success", ipcname));
    }

    return rc;
} /* end _MD_DeleteSharedMemory() */
#endif

/*
** Unix implementation for anonymous memory (file) mapping
*/
extern PRLogModuleInfo* _pr_shma_lm;

#include <unistd.h>

extern PRFileMap*
_md_OpenAnonFileMap(const char* dirName, PRSize size,
                    PRFileMapProtect prot)
{
    PRFileMap* fm = NULL;
    PRFileDesc* fd;
    int osfd;
    PRIntn urc;
    PRIntn mode = 0600;
    char* genName;
    pid_t pid = getpid();                  /* for generating filename */
    PRThread* tid = PR_GetCurrentThread(); /* for generating filename */
    int incr;                              /* for generating filename */
    const int maxTries = 20;               /* maximum # attempts at a unique filename */
    PRInt64 size64;                        /* 64-bit version of 'size' */

    /*
    ** generate a filename from input and runtime environment
    ** open the file, unlink the file.
    ** make maxTries number of attempts at uniqueness in the filename
    */
    for (incr = 0; incr < maxTries; incr++) {
#define NSPR_AFM_FILENAME "%s/.NSPR-AFM-%d-%p.%d"
        genName = PR_smprintf(NSPR_AFM_FILENAME, dirName, (int)pid, tid, incr);
        if (NULL == genName) {
            PR_LOG(_pr_shma_lm, PR_LOG_DEBUG,
                   ("_md_OpenAnonFileMap(): PR_snprintf(): failed, generating "
                    "filename"));
            goto Finished;
        }

        /* create the file */
        osfd = open(genName, (O_CREAT | O_EXCL | O_RDWR), mode);
        if (-1 == osfd) {
            if (EEXIST == errno) {
                PR_smprintf_free(genName);
                continue; /* name exists, try again */
            }
            _PR_MD_MAP_OPEN_ERROR(errno);
            PR_LOG(_pr_shma_lm, PR_LOG_DEBUG,
                   ("_md_OpenAnonFileMap(): open(): failed, filename: %s, errno: %d",
                    genName, PR_GetOSError()));
            PR_smprintf_free(genName);
            goto Finished;
        }
        break; /* name generation and open successful, break; */
    } /* end for() */

    if (incr == maxTries) {
        PR_ASSERT(-1 == osfd);
        PR_ASSERT(EEXIST == errno);
        _PR_MD_MAP_OPEN_ERROR(errno);
        goto Finished;
    }

    urc = unlink(genName);
    if (-1 == urc) {
        _PR_MD_MAP_UNLINK_ERROR(errno);
        PR_LOG(_pr_shma_lm, PR_LOG_DEBUG,
               ("_md_OpenAnonFileMap(): failed on unlink(), errno: %d", errno));
        PR_smprintf_free(genName);
        close(osfd);
        goto Finished;
    }
    PR_LOG(_pr_shma_lm, PR_LOG_DEBUG,
           ("_md_OpenAnonFileMap(): unlink(): %s", genName));

    PR_smprintf_free(genName);

    fd = PR_ImportFile(osfd);
    if (NULL == fd) {
        PR_LOG(_pr_shma_lm, PR_LOG_DEBUG,
               ("_md_OpenAnonFileMap(): PR_ImportFile(): failed"));
        goto Finished;
    }
    PR_LOG(_pr_shma_lm, PR_LOG_DEBUG, ("_md_OpenAnonFileMap(): fd: %p", fd));

    urc = ftruncate(fd->secret->md.osfd, size);
    if (-1 == urc) {
        _PR_MD_MAP_DEFAULT_ERROR(errno);
        PR_LOG(_pr_shma_lm, PR_LOG_DEBUG,
               ("_md_OpenAnonFileMap(): failed on ftruncate(), errno: %d", errno));
        PR_Close(fd);
        goto Finished;
    }
    PR_LOG(_pr_shma_lm, PR_LOG_DEBUG,
           ("_md_OpenAnonFileMap(): ftruncate(): size: %d", size));

    LL_UI2L(size64, size); /* PRSize (size_t) is unsigned */
    fm = PR_CreateFileMap(fd, size64, prot);
    if (NULL == fm) {
        PR_LOG(_pr_shma_lm, PR_LOG_DEBUG, ("PR_OpenAnonFileMap(): failed"));
        PR_Close(fd);
        goto Finished;
    }
    fm->md.isAnonFM = PR_TRUE; /* set fd close */

    PR_LOG(_pr_shma_lm, PR_LOG_DEBUG,
           ("_md_OpenAnonFileMap(): PR_CreateFileMap(): fm: %p", fm));

Finished:
    return (fm);
} /* end md_OpenAnonFileMap() */

/*
** _md_ExportFileMapAsString()
**
**
*/
extern PRStatus
_md_ExportFileMapAsString(PRFileMap* fm, PRSize bufSize,
                          char* buf)
{
    PRIntn written;
    PRIntn prot = (PRIntn)fm->prot;

    written = PR_snprintf(buf, bufSize, "%ld:%d", fm->fd->secret->md.osfd, prot);

    return ((written == -1) ? PR_FAILURE : PR_SUCCESS);
} /* end _md_ExportFileMapAsString() */

extern PRFileMap*
_md_ImportFileMapFromString(const char* fmstring)
{
    PRStatus rc;
    PRInt32 osfd;
    PRIntn prot; /* really: a PRFileMapProtect */
    PRFileDesc* fd;
    PRFileMap* fm = NULL; /* default return value */
    PRFileInfo64 info;

    PR_sscanf(fmstring, "%ld:%d", &osfd, &prot);

    /* import the os file descriptor */
    fd = PR_ImportFile(osfd);
    if (NULL == fd) {
        PR_LOG(_pr_shma_lm, PR_LOG_DEBUG,
               ("_md_ImportFileMapFromString(): PR_ImportFile() failed"));
        goto Finished;
    }

    rc = PR_GetOpenFileInfo64(fd, &info);
    if (PR_FAILURE == rc) {
        PR_LOG(_pr_shma_lm, PR_LOG_DEBUG,
               ("_md_ImportFileMapFromString(): PR_GetOpenFileInfo64() failed"));
        goto Finished;
    }

    fm = PR_CreateFileMap(fd, info.size, (PRFileMapProtect)prot);
    if (NULL == fm) {
        PR_LOG(_pr_shma_lm, PR_LOG_DEBUG,
               ("_md_ImportFileMapFromString(): PR_CreateFileMap() failed"));
    }

Finished:
    return (fm);
} /* end _md_ImportFileMapFromString() */
