filestat.c

apr-1.2.7.tar.gz源码 支持svn的需求

/* Copyright 2000-2005 The Apache Software Foundation or its licensors, as
 * applicable.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "apr.h"
#include <aclapi.h>
#include "apr_private.h"
#include "apr_arch_file_io.h"
#include "apr_file_io.h"
#include "apr_general.h"
#include "apr_strings.h"
#include "apr_errno.h"
#include "apr_time.h"
#include <sys/stat.h>
#include "apr_arch_atime.h"
#include "apr_arch_misc.h"

/* We have to assure that the file name contains no '*'s, or other
 * wildcards when using FindFirstFile to recover the true file name.
 */
static apr_status_t test_safe_name(const char *name)
{
    /* Only accept ':' in the second position of the filename,
     * as the drive letter delimiter:
     */
    if (apr_isalpha(*name) && (name[1] == ':')) {
        name += 2;
    }
    while (*name) {
        if (!IS_FNCHAR(*name) && (*name != '\\') && (*name != '/')) {
            if (*name == '?' || *name == '*')
                return APR_EPATHWILD;
            else
                return APR_EBADPATH;
        }
        ++name;
    }
    return APR_SUCCESS;
}

static apr_status_t free_localheap(void *heap) {
    LocalFree(heap);
    return APR_SUCCESS;
}

static apr_gid_t worldid = NULL;

static void free_world(void)
{
    if (worldid) {
        FreeSid(worldid);
        worldid = NULL;
    }
}

/* Left bit shifts from World scope to given scope */
typedef enum prot_scope_e {
    prot_scope_world = 0,
    prot_scope_group = 4,
    prot_scope_user =  8
} prot_scope_e;

static apr_fileperms_t convert_prot(ACCESS_MASK acc, prot_scope_e scope)
{
    /* These choices are based on the single filesystem bit that controls
     * the given behavior.  They are -not- recommended for any set protection
     * function, such a function should -set- use GENERIC_READ/WRITE/EXECUTE
     */
    apr_fileperms_t prot = 0;
    if (acc & FILE_EXECUTE)
        prot |= APR_WEXECUTE;
    if (acc & FILE_WRITE_DATA)
        prot |= APR_WWRITE;
    if (acc & FILE_READ_DATA)
        prot |= APR_WREAD;
    return (prot << scope);
}

static void resolve_prot(apr_finfo_t *finfo, apr_int32_t wanted, PACL dacl)
{
    TRUSTEE_W ident = {NULL, NO_MULTIPLE_TRUSTEE, TRUSTEE_IS_SID};
    ACCESS_MASK acc;
    /*
     * This function is only invoked for WinNT, 
     * there is no reason for os_level testing here.
     */
    if ((wanted & APR_FINFO_WPROT) && !worldid) {
        SID_IDENTIFIER_AUTHORITY SIDAuth = SECURITY_WORLD_SID_AUTHORITY;
        if (AllocateAndInitializeSid(&SIDAuth, 1, SECURITY_WORLD_RID,
                                     0, 0, 0, 0, 0, 0, 0, &worldid))
            atexit(free_world);
        else
            worldid = NULL;
    }
    if ((wanted & APR_FINFO_UPROT) && (finfo->valid & APR_FINFO_USER)) {
        ident.TrusteeType = TRUSTEE_IS_USER;
        ident.ptstrName = finfo->user;
        /* GetEffectiveRightsFromAcl isn't supported under Win9x,
         * which shouldn't come as a surprize.  Since we are passing
         * TRUSTEE_IS_SID, always skip the A->W layer.
         */
        if (GetEffectiveRightsFromAclW(dacl, &ident, &acc) == ERROR_SUCCESS) {
            finfo->protection |= convert_prot(acc, prot_scope_user);
            finfo->valid |= APR_FINFO_UPROT;
        }
    }
    /* Windows NT: did not return group rights.
     * Windows 2000 returns group rights information.
     * Since WinNT kernels don't follow the unix model of 
     * group associations, this all all pretty mute.
     */
    if ((wanted & APR_FINFO_GPROT) && (finfo->valid & APR_FINFO_GROUP)) {
        ident.TrusteeType = TRUSTEE_IS_GROUP;
        ident.ptstrName = finfo->group;
        if (GetEffectiveRightsFromAclW(dacl, &ident, &acc) == ERROR_SUCCESS) {
            finfo->protection |= convert_prot(acc, prot_scope_group);
            finfo->valid |= APR_FINFO_GPROT;
        }
    }
    if ((wanted & APR_FINFO_WPROT) && (worldid)) {
        ident.TrusteeType = TRUSTEE_IS_WELL_KNOWN_GROUP;
        ident.ptstrName = worldid;
        if (GetEffectiveRightsFromAclW(dacl, &ident, &acc) == ERROR_SUCCESS) {
            finfo->protection |= convert_prot(acc, prot_scope_world);
            finfo->valid |= APR_FINFO_WPROT;
        }
    }
}

static apr_status_t resolve_ident(apr_finfo_t *finfo, const char *fname,
                                  apr_int32_t wanted, apr_pool_t *pool)
{
    apr_file_t *thefile = NULL;
    apr_status_t rv;
    /* 
     * NT5 (W2K) only supports symlinks in the same manner as mount points.
     * This code should eventually take that into account, for now treat
     * every reparse point as a symlink...
     *
     * We must open the file with READ_CONTROL if we plan to retrieve the
     * user, group or permissions.
     */
    
    if ((rv = apr_file_open(&thefile, fname, APR_OPENINFO
                          | ((wanted & APR_FINFO_LINK) ? APR_OPENLINK : 0)
                          | ((wanted & (APR_FINFO_PROT | APR_FINFO_OWNER))
                                ? APR_READCONTROL : 0),
                            APR_OS_DEFAULT, pool)) == APR_SUCCESS) {
        rv = apr_file_info_get(finfo, wanted, thefile);
        finfo->filehand = NULL;
        apr_file_close(thefile);
    }
    else if (APR_STATUS_IS_EACCES(rv) && (wanted & (APR_FINFO_PROT 
                                                  | APR_FINFO_OWNER))) {
        /* We have a backup plan.  Perhaps we couldn't grab READ_CONTROL?
         * proceed without asking for that permission...
         */
        if ((rv = apr_file_open(&thefile, fname, APR_OPENINFO
                              | ((wanted & APR_FINFO_LINK) ? APR_OPENLINK : 0),
                                APR_OS_DEFAULT, pool)) == APR_SUCCESS) {
            rv = apr_file_info_get(finfo, wanted & ~(APR_FINFO_PROT 
                                                 | APR_FINFO_OWNER),
                                 thefile);
            finfo->filehand = NULL;
            apr_file_close(thefile);
        }
    }

    if (rv != APR_SUCCESS && rv != APR_INCOMPLETE)
        return (rv);

    /* We picked up this case above and had opened the link's properties */
    if (wanted & APR_FINFO_LINK)
        finfo->valid |= APR_FINFO_LINK;

    return rv;
}

static void guess_protection_bits(apr_finfo_t *finfo)
{
    /* Read, write execute for owner.  In the Win9x environment, any
     * readable file is executable (well, not entirely 100% true, but
     * still looking for some cheap logic that would help us here.)
     * The same holds on NT if a file doesn't have a DACL (e.g., on FAT)
     */
    if (finfo->protection & APR_FREADONLY) {
        finfo->protection |= APR_WREAD | APR_WEXECUTE;
    }
    else {
        finfo->protection |= APR_WREAD | APR_WEXECUTE | APR_WWRITE;
    }
    finfo->protection |= (finfo->protection << prot_scope_group)
                       | (finfo->protection << prot_scope_user);

    finfo->valid |= APR_FINFO_UPROT | APR_FINFO_GPROT | APR_FINFO_WPROT;
}

apr_status_t more_finfo(apr_finfo_t *finfo, const void *ufile, 
                        apr_int32_t wanted, int whatfile)
{
    PSID user = NULL, grp = NULL;
    PACL dacl = NULL;
    apr_status_t rv;

    if (apr_os_level < APR_WIN_NT)
        guess_protection_bits(finfo);
    else if (wanted & (APR_FINFO_PROT | APR_FINFO_OWNER))
    {
        /* On NT this request is incredibly expensive, but accurate.
         * Since the WinNT-only functions below are protected by the
         * (apr_os_level < APR_WIN_NT) case above, we need no extra
         * tests, but remember GetNamedSecurityInfo & GetSecurityInfo
         * are not supported on 9x.
         */
        SECURITY_INFORMATION sinf = 0;
        PSECURITY_DESCRIPTOR pdesc = NULL;
        if (wanted & (APR_FINFO_USER | APR_FINFO_UPROT))
            sinf |= OWNER_SECURITY_INFORMATION;
        if (wanted & (APR_FINFO_GROUP | APR_FINFO_GPROT))
            sinf |= GROUP_SECURITY_INFORMATION;
        if (wanted & APR_FINFO_PROT)
            sinf |= DACL_SECURITY_INFORMATION;
        if (whatfile == MORE_OF_WFSPEC) {
            apr_wchar_t *wfile = (apr_wchar_t*) ufile;
            int fix = 0;
            if (wcsncmp(wfile, L"\\\\?\\", 4) == 0) {
                fix = 4;
                if (wcsncmp(wfile + fix, L"UNC\\", 4) == 0)
                    wfile[6] = L'\\', fix = 6;
            }
            rv = GetNamedSecurityInfoW(wfile + fix, 
                                 SE_FILE_OBJECT, sinf,
                                 ((wanted & APR_FINFO_USER) ? &user : NULL),
                                 ((wanted & APR_FINFO_GROUP) ? &grp : NULL),
                                 ((wanted & APR_FINFO_PROT) ? &dacl : NULL),
                                 NULL, &pdesc);
            if (fix == 6)
                wfile[6] = L'C';
        }
        else if (whatfile == MORE_OF_FSPEC)
            rv = GetNamedSecurityInfoA((char*)ufile, 
                                 SE_FILE_OBJECT, sinf,
                                 ((wanted & APR_FINFO_USER) ? &user : NULL),
                                 ((wanted & APR_FINFO_GROUP) ? &grp : NULL),
                                 ((wanted & APR_FINFO_PROT) ? &dacl : NULL),
                                 NULL, &pdesc);
        else if (whatfile == MORE_OF_HANDLE)
            rv = GetSecurityInfo((HANDLE)ufile, 
                                 SE_FILE_OBJECT, sinf,
                                 ((wanted & APR_FINFO_USER) ? &user : NULL),
                                 ((wanted & APR_FINFO_GROUP) ? &grp : NULL),
                                 ((wanted & APR_FINFO_PROT) ? &dacl : NULL),
                                 NULL, &pdesc);
        else
            return APR_INCOMPLETE;
        if (rv == ERROR_SUCCESS)
            apr_pool_cleanup_register(finfo->pool, pdesc, free_localheap, 
                                 apr_pool_cleanup_null);
        else
            user = grp = dacl = NULL;

        if (user) {
            finfo->user = user;
            finfo->valid |= APR_FINFO_USER;
        }

        if (grp) {
            finfo->group = grp;
            finfo->valid |= APR_FINFO_GROUP;
        }

        if (dacl) {
            /* Retrieved the discresionary access list */
            resolve_prot(finfo, wanted, dacl);
        }
        else if (wanted & APR_FINFO_PROT)
            guess_protection_bits(finfo);
    }

    return ((wanted & ~finfo->valid) ? APR_INCOMPLETE : APR_SUCCESS);
}


/* This generic fillin depends upon byhandle to be passed as 0 when
 * a WIN32_FILE_ATTRIBUTE_DATA or either WIN32_FIND_DATA [A or W] is
 * passed for wininfo.  When the BY_HANDLE_FILE_INFORMATION structure
 * is passed for wininfo, byhandle is passed as 1 to offset the one
 * dword discrepancy in offset of the High/Low size structure members.
 *
 * The generic fillin returns 1 if the caller should further inquire
 * if this is a CHR filetype.  If it's reasonably certain it can't be,
 * then the function returns 0.
 */
int fillin_fileinfo(apr_finfo_t *finfo, 
                    WIN32_FILE_ATTRIBUTE_DATA *wininfo, 
                    int byhandle, apr_int32_t wanted) 
{
    DWORD *sizes = &wininfo->nFileSizeHigh + byhandle;
    int warn = 0;

    memset(finfo, '\0', sizeof(*finfo));

    FileTimeToAprTime(&finfo->atime, &wininfo->ftLastAccessTime);
    FileTimeToAprTime(&finfo->ctime, &wininfo->ftCreationTime);
    FileTimeToAprTime(&finfo->mtime, &wininfo->ftLastWriteTime);

#if APR_HAS_LARGE_FILES
    finfo->size =  (apr_off_t)sizes[1]
                | ((apr_off_t)sizes[0] << 32);
#else
    finfo->size = (apr_off_t)sizes[1];
    if (finfo->size < 0 || sizes[0])
        finfo->size = 0x7fffffff;
#endif

    if (wanted & APR_FINFO_LINK &&
        wininfo->dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
        finfo->filetype = APR_LNK;
    }
    else if (wininfo->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) {
        finfo->filetype = APR_DIR;
    }
    else if (wininfo->dwFileAttributes & FILE_ATTRIBUTE_DEVICE) {
        /* Warning: This test only succeeds on Win9x, on NT these files
         * (con, aux, nul, lpt#, com# etc) escape early detection!
         */
        finfo->filetype = APR_CHR;
    }
    else {
        /* Warning: Short of opening the handle to the file, the 'FileType'
         * appears to be unknowable (in any trustworthy or consistent sense)
         * on WinNT/2K as far as PIPE, CHR, etc are concerned.
         */
        if (!wininfo->ftLastWriteTime.dwLowDateTime 
                && !wininfo->ftLastWriteTime.dwHighDateTime 
                && !finfo->size)
            warn = 1;
        finfo->filetype = APR_REG;
    }

    /* The following flags are [for this moment] private to Win32.
     * That's the only excuse for not toggling valid bits to reflect them.
     */
    if (wininfo->dwFileAttributes & FILE_ATTRIBUTE_READONLY)
        finfo->protection = APR_FREADONLY;
    
    finfo->valid = APR_FINFO_ATIME | APR_FINFO_CTIME | APR_FINFO_MTIME
                 | APR_FINFO_SIZE  | APR_FINFO_TYPE;   /* == APR_FINFO_MIN */

    /* Only byhandle optionally tests link targets, so tell that caller
     * what it wants to hear, otherwise the byattributes is never
     * reporting anything but the link.
     */
    if (!byhandle || (wanted & APR_FINFO_LINK))
        finfo->valid |= APR_FINFO_LINK;
    return warn;
}


APR_DECLARE(apr_status_t) apr_file_info_get(apr_finfo_t *finfo, apr_int32_t wanted,
                                            apr_file_t *thefile)
{
    BY_HANDLE_FILE_INFORMATION FileInfo;

    if (thefile->buffered) {
        /* XXX: flush here is not mutex protected */
        apr_status_t rv = apr_file_flush(thefile);
        if (rv != APR_SUCCESS)
            return rv;