format.c

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/*
 * Implementation of the Microsoft Installer (msi.dll)
 *
 * Copyright 2005 Mike McCormack for CodeWeavers
 * Copyright 2005 Aric Stewart for CodeWeavers
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */

#include <stdarg.h>
#include <stdio.h>

#define COBJMACROS

#include "windef.h"
#include "winbase.h"
#include "winerror.h"
#include "wine/debug.h"
#include "msi.h"
#include "winnls.h"
#include "objbase.h"
#include "oleauto.h"

#include "msipriv.h"
#include "msiserver.h"
#include "wine/unicode.h"

WINE_DEFAULT_DEBUG_CHANNEL(msi);

/* types arranged by precedence */
#define FORMAT_NULL         0x0001
#define FORMAT_LITERAL      0x0002
#define FORMAT_NUMBER       0x0004
#define FORMAT_LBRACK       0x0010
#define FORMAT_LBRACE       0x0020
#define FORMAT_RBRACK       0x0011
#define FORMAT_RBRACE       0x0021
#define FORMAT_ESCAPE       0x0040
#define FORMAT_PROPNULL     0x0080
#define FORMAT_ERROR        0x1000
#define FORMAT_FAIL         0x2000

#define left_type(x) (x & 0xF0)

typedef struct _tagFORMAT
{
    MSIPACKAGE *package;
    MSIRECORD *record;
    LPWSTR deformatted;
    int len;
    int n;
    BOOL propfailed;
    BOOL groupfailed;
    int groups;
} FORMAT;

typedef struct _tagFORMSTR
{
    struct list entry;
    int n;
    int len;
    int type;
    BOOL propfound;
    BOOL nonprop;
} FORMSTR;

typedef struct _tagSTACK
{
    struct list items;
} STACK;

static STACK *create_stack(void)
{
    STACK *stack = msi_alloc(sizeof(STACK));
    list_init(&stack->items);
    return stack;
}

static void free_stack(STACK *stack)
{
    while (!list_empty(&stack->items))
    {
        FORMSTR *str = LIST_ENTRY(list_head(&stack->items), FORMSTR, entry);
        list_remove(&str->entry);
        msi_free(str);
    }

    msi_free(stack);
}

static void stack_push(STACK *stack, FORMSTR *str)
{
    list_add_head(&stack->items, &str->entry);
}

static FORMSTR *stack_pop(STACK *stack)
{
    FORMSTR *ret;

    if (list_empty(&stack->items))
        return NULL;

    ret = LIST_ENTRY(list_head(&stack->items), FORMSTR, entry);
    list_remove(&ret->entry);
    return ret;
}

static FORMSTR *stack_find(STACK *stack, int type)
{
    FORMSTR *str;

    LIST_FOR_EACH_ENTRY(str, &stack->items, FORMSTR, entry)
    {
        if (str->type == type)
            return str;
    }

    return NULL;
}

static FORMSTR *stack_peek(STACK *stack)
{
    return LIST_ENTRY(list_head(&stack->items), FORMSTR, entry);
}

static LPCWSTR get_formstr_data(FORMAT *format, FORMSTR *str)
{
    return &format->deformatted[str->n];
}

static WCHAR *dup_formstr( FORMAT *format, FORMSTR *str, int *ret_len )
{
    WCHAR *val;

    if (!str->len) return NULL;
    if ((val = msi_alloc( (str->len + 1) * sizeof(WCHAR) )))
    {
        memcpy( val, get_formstr_data(format, str), str->len * sizeof(WCHAR) );
        val[str->len] = 0;
        *ret_len = str->len;
    }
    return val;
}

static WCHAR *deformat_index( FORMAT *format, FORMSTR *str, int *ret_len )
{
    WCHAR *val, *ret;
    DWORD len;
    int field;

    if (!(val = msi_alloc( (str->len + 1) * sizeof(WCHAR) ))) return NULL;
    lstrcpynW(val, get_formstr_data(format, str), str->len + 1);
    field = atoiW( val );
    msi_free( val );

    if (MSI_RecordIsNull( format->record, field ) ||
        MSI_RecordGetStringW( format->record, field, NULL, &len )) return NULL;

    len++;
    if (!(ret = msi_alloc( len * sizeof(WCHAR) ))) return NULL;
    ret[0] = 0;
    if (MSI_RecordGetStringW( format->record, field, ret, &len ))
    {
        msi_free( ret );
        return NULL;
    }
    *ret_len = len;
    return ret;
}

static WCHAR *deformat_property( FORMAT *format, FORMSTR *str, int *ret_len )
{
    WCHAR *prop, *ret;
    DWORD len = 0;
    UINT r;

    if (!(prop = msi_alloc( (str->len + 1) * sizeof(WCHAR) ))) return NULL;
    lstrcpynW( prop, get_formstr_data(format, str), str->len + 1 );

    r = msi_get_property( format->package->db, prop, NULL, &len );
    if (r != ERROR_SUCCESS && r != ERROR_MORE_DATA)
    {
        msi_free( prop );
        return NULL;
    }
    len++;
    if ((ret = msi_alloc( len * sizeof(WCHAR) )))
        msi_get_property( format->package->db, prop, ret, &len );
    msi_free( prop );
    *ret_len = len;
    return ret;
}

static WCHAR *deformat_component( FORMAT *format, FORMSTR *str, int *ret_len )
{
    WCHAR *key, *ret;
    MSICOMPONENT *comp;

    if (!(key = msi_alloc( (str->len + 1) * sizeof(WCHAR) ))) return NULL;
    lstrcpynW(key, get_formstr_data(format, str), str->len + 1);

    if (!(comp = msi_get_loaded_component( format->package, key )))
    {
        msi_free( key );
        return NULL;
    }
    if (comp->Action == INSTALLSTATE_SOURCE)
        ret = msi_resolve_source_folder( format->package, comp->Directory, NULL );
    else
        ret = strdupW( msi_get_target_folder( format->package, comp->Directory ) );

    if (ret) *ret_len = strlenW( ret );
    else *ret_len = 0;
    msi_free( key );
    return ret;
}

static WCHAR *deformat_file( FORMAT *format, FORMSTR *str, BOOL shortname, int *ret_len )
{
    WCHAR *key, *ret = NULL;
    const MSIFILE *file;
    DWORD len = 0;

    if (!(key = msi_alloc( (str->len + 1) * sizeof(WCHAR) ))) return NULL;
    lstrcpynW(key, get_formstr_data(format, str), str->len + 1);

    if (!(file = msi_get_loaded_file( format->package, key ))) goto done;
    if (!shortname)
    {
        if ((ret = strdupW( file->TargetPath ))) len = strlenW( ret );
        goto done;
    }
    if ((len = GetShortPathNameW(file->TargetPath, NULL, 0)) <= 0)
    {
        if ((ret = strdupW( file->TargetPath ))) len = strlenW( ret );
        goto done;
    }
    len++;
    if ((ret = msi_alloc( len * sizeof(WCHAR) )))
        len = GetShortPathNameW( file->TargetPath, ret, len );

done:
    msi_free( key );
    *ret_len = len;
    return ret;
}

static WCHAR *deformat_environment( FORMAT *format, FORMSTR *str, int *ret_len )
{
    WCHAR *key, *ret = NULL;
    DWORD len;

    if (!(key = msi_alloc((str->len + 1) * sizeof(WCHAR)))) return NULL;
    lstrcpynW(key, get_formstr_data(format, str), str->len + 1);

    if ((len = GetEnvironmentVariableW( key, NULL, 0 )))
    {
        len++;
        if ((ret = msi_alloc( len * sizeof(WCHAR) )))
            *ret_len = GetEnvironmentVariableW( key, ret, len );
    }
    msi_free( key );
    return ret;
}

static WCHAR *deformat_literal( FORMAT *format, FORMSTR *str, BOOL *propfound,
                                int *type, int *len )
{
    LPCWSTR data = get_formstr_data(format, str);
    WCHAR *replaced = NULL;
    char ch = data[0];

    if (ch == '\\')
    {
        str->n++;
        if (str->len == 1)
        {
            str->len = 0;
            replaced = NULL;
        }
        else
        {
            str->len = 1;
            replaced = dup_formstr( format, str, len );
        }
    }
    else if (ch == '~')
    {
        if (str->len != 1)
            replaced = NULL;
        else if ((replaced = msi_alloc( sizeof(WCHAR) )))
        {
            *replaced = 0;
            *len = 0;
        }
    }
    else if (ch == '%' || ch == '#' || ch == '!' || ch == '$')
    {
        str->n++;
        str->len--;

        switch (ch)
        {
        case '%':
            replaced = deformat_environment( format, str, len ); break;
        case '#':
            replaced = deformat_file( format, str, FALSE, len ); break;
        case '!':
            replaced = deformat_file( format, str, TRUE, len ); break;
        case '$':
            replaced = deformat_component( format, str, len ); break;
        }

        *type = FORMAT_LITERAL;
    }
    else
    {
        replaced = deformat_property( format, str, len );
        *type = FORMAT_LITERAL;

        if (replaced)
            *propfound = TRUE;
        else
            format->propfailed = TRUE;
    }

    return replaced;
}

static WCHAR *build_default_format( const MSIRECORD *record )
{
    static const WCHAR fmt[] = {'%','i',':',' ','[','%','i',']',' ',0};
    int i, count = MSI_RecordGetFieldCount( record );
    WCHAR *ret, *tmp, buf[26];
    DWORD size = 1;

    if (!(ret = msi_alloc( sizeof(*ret) ))) return NULL;
    ret[0] = 0;

    for (i = 1; i <= count; i++)
    {
        size += sprintfW( buf, fmt, i, i );
        if (!(tmp = msi_realloc( ret, size * sizeof(*ret) )))
        {
            msi_free( ret );
            return NULL;
        }
        ret = tmp;
        strcatW( ret, buf );
    }
    return ret;
}

static BOOL format_is_number(WCHAR x)
{
    return ((x >= '0') && (x <= '9'));
}

static BOOL format_str_is_number(LPWSTR str)
{
    LPWSTR ptr;

    for (ptr = str; *ptr; ptr++)
        if (!format_is_number(*ptr))
            return FALSE;

    return TRUE;
}

static BOOL format_is_alpha(WCHAR x)
{
    return (!format_is_number(x) && x != '\0' &&
            x != '[' && x != ']' && x != '{' && x != '}');
}

static BOOL format_is_literal(WCHAR x)
{
    return (format_is_alpha(x) || format_is_number(x));
}

static int format_lex(FORMAT *format, FORMSTR **out)
{
    int type, len = 1;
    FORMSTR *str;
    LPCWSTR data;
    WCHAR ch;

    *out = NULL;

    if (!format->deformatted)
        return FORMAT_NULL;

    *out = msi_alloc_zero(sizeof(FORMSTR));
    if (!*out)
        return FORMAT_FAIL;

    str = *out;
    str->n = format->n;
    str->len = 1;
    data = get_formstr_data(format, str);

    ch = data[0];
    switch (ch)
    {
        case '{': type = FORMAT_LBRACE; break;
        case '}': type = FORMAT_RBRACE; break;
        case '[': type = FORMAT_LBRACK; break;
        case ']': type = FORMAT_RBRACK; break;
        case '~': type = FORMAT_PROPNULL; break;
        case '\0': type = FORMAT_NULL; break;

        default:
            type = 0;
    }

    if (type)
    {
        str->type = type;
        format->n++;
        return type;
    }

    if (ch == '\\')
    {
        while (data[len] && data[len] != ']')
            len++;

        type = FORMAT_ESCAPE;
    }
    else if (format_is_alpha(ch))
    {
        while (format_is_literal(data[len]))
            len++;

        type = FORMAT_LITERAL;
    }
    else if (format_is_number(ch))
    {
        while (format_is_number(data[len]))
            len++;

        type = FORMAT_NUMBER;

        if (data[len] != ']')
        {
            while (format_is_literal(data[len]))
                len++;

            type = FORMAT_LITERAL;
        }
    }
    else
    {
        ERR("Got unknown character %c(%x)\n", ch, ch);
        return FORMAT_ERROR;
    }

    format->n += len;
    str->len = len;
    str->type = type;

    return type;
}

static FORMSTR *format_replace( FORMAT *format, BOOL propfound, BOOL nonprop,
                                int oldsize, int type, WCHAR *replace, int len )
{
    FORMSTR *ret;
    LPWSTR str, ptr;
    DWORD size = 0;
    int n;

    if (replace)
    {
        if (!len)
            size = 1;
        else
            size = len;
    }

    size -= oldsize;
    size = format->len + size + 1;

    if (size <= 1)
    {
        msi_free(format->deformatted);
        format->deformatted = NULL;
        format->len = 0;
        return NULL;
    }

    str = msi_alloc(size * sizeof(WCHAR));
    if (!str)
        return NULL;

    str[0] = '\0';
    memcpy(str, format->deformatted, format->n * sizeof(WCHAR));
    n = format->n;

    if (replace)
    {
        if (!len) str[n++] = 0;
        else
        {
            memcpy( str + n, replace, len * sizeof(WCHAR) );
            n += len;
            str[n] = 0;
        }
    }

    ptr = &format->deformatted[format->n + oldsize];
    memcpy(&str[n], ptr, (lstrlenW(ptr) + 1) * sizeof(WCHAR));

    msi_free(format->deformatted);
    format->deformatted = str;
    format->len = size - 1;

    /* don't reformat the NULL */
    if (replace && !len)
        format->n++;

    if (!replace)
        return NULL;

    ret = msi_alloc_zero(sizeof(FORMSTR));
    if (!ret)
        return NULL;

    ret->len = len;
    ret->type = type;
    ret->n = format->n;
    ret->propfound = propfound;
    ret->nonprop = nonprop;

    return ret;
}

static WCHAR *replace_stack_group( FORMAT *format, STACK *values,
                                   BOOL *propfound, BOOL *nonprop,
                                   int *oldsize, int *type, int *len )
{
    WCHAR *replaced;
    FORMSTR *content, *node;
    int n;

    *nonprop = FALSE;
    *propfound = FALSE;

    node = stack_pop(values);
    n = node->n;
    *oldsize = node->len;
    msi_free(node);

    while ((node = stack_pop(values)))
    {
        *oldsize += node->len;

        if (node->nonprop)
            *nonprop = TRUE;

        if (node->propfound)
            *propfound = TRUE;

        msi_free(node);
    }

    content = msi_alloc_zero(sizeof(FORMSTR));
    content->n = n;
    content->len = *oldsize;
    content->type = FORMAT_LITERAL;

    if (!format->groupfailed && (*oldsize == 2 ||
        (format->propfailed && !*nonprop)))
    {
        msi_free(content);
        return NULL;
    }
    else if (format->deformatted[content->n + 1] == '{' &&
             format->deformatted[content->n + content->len - 2] == '}')
    {
        format->groupfailed = FALSE;
        content->len = 0;
    }
    else if (*propfound && !*nonprop &&
             !format->groupfailed && format->groups == 0)
    {
        content->n++;
        content->len -= 2;
    }
    else
    {
        if (format->groups != 0)
            format->groupfailed = TRUE;

        *nonprop = TRUE;
    }

    replaced = dup_formstr( format, content, len );
    *type = content->type;
    msi_free(content);

    if (format->groups == 0)
        format->propfailed = FALSE;

    return replaced;
}

static WCHAR *replace_stack_prop( FORMAT *format, STACK *values,
                                  BOOL *propfound, BOOL *nonprop,
                                  int *oldsize, int *type, int *len )
{
    WCHAR *replaced;
    FORMSTR *content, *node;
    int n;

    *propfound = FALSE;
    *nonprop = FALSE;

    node = stack_pop(values);
    n = node->n;
    *oldsize = node->len;
    *type = stack_peek(values)->type;
    msi_free(node);

    while ((node = stack_pop(values)))
    {
        *oldsize += node->len;

        if (*type != FORMAT_ESCAPE &&
            stack_peek(values) && node->type != *type)
            *type = FORMAT_LITERAL;

        msi_free(node);
    }

    content = msi_alloc_zero(sizeof(FORMSTR));
    content->n = n + 1;
    content->len = *oldsize - 2;
    content->type = *type;

    if (*type == FORMAT_NUMBER && format->record)
    {
        replaced = deformat_index( format, content, len );
        if (replaced)
            *propfound = TRUE;
        else
            format->propfailed = TRUE;

        if (replaced)
            *type = format_str_is_number(replaced) ?
                FORMAT_NUMBER : FORMAT_LITERAL;
    }
    else if (format->package)
    {
        replaced = deformat_literal( format, content, propfound, type, len );
    }
    else
    {
        *nonprop = TRUE;
        content->n--;
        content->len += 2;
        replaced = dup_formstr( format, content, len );
    }
    msi_free(content);
    return replaced;
}

static UINT replace_stack(FORMAT *format, STACK *stack, STACK *values)
{
    WCHAR *replaced = NULL;
    FORMSTR *beg, *top, *node;
    BOOL propfound = FALSE, nonprop = FALSE, group = FALSE;
    int type, n, len = 0, oldsize = 0;

    node = stack_peek(values);
    type = node->type;
    n = node->n;

    if (type == FORMAT_LBRACK)
        replaced = replace_stack_prop( format, values, &propfound,
                                       &nonprop, &oldsize, &type, &len );
    else if (type == FORMAT_LBRACE)
    {
        replaced = replace_stack_group( format, values, &propfound,
                                        &nonprop, &oldsize, &type, &len );
        group = TRUE;
    }

    format->n = n;
    beg = format_replace( format, propfound, nonprop, oldsize, type, replaced, len );
    msi_free(replaced);
    if (!beg)
        return ERROR_SUCCESS;

    format->n = beg->n + beg->len;

    top = stack_peek(stack);
    if (top)
    {
        type = top->type;

        if ((type == FORMAT_LITERAL || type == FORMAT_NUMBER) &&
            type == beg->type)
        {
            top->len += beg->len;

            if (group)
                top->nonprop = FALSE;

            if (type == FORMAT_LITERAL)
                top->nonprop = beg->nonprop;

            if (beg->propfound)
                top->propfound = TRUE;

            msi_free(beg);
            return ERROR_SUCCESS;
        }
    }

    stack_push(stack, beg);
    return ERROR_SUCCESS;
}

static BOOL verify_format(LPWSTR data)
{
    int count = 0;

    while (*data)
    {
        if (*data == '[' && *(data - 1) != '\\')
            count++;
        else if (*data == ']')
            count--;

        data++;
    }

    if (count > 0)
        return FALSE;

    return TRUE;
}

static DWORD deformat_string_internal(MSIPACKAGE *package, LPCWSTR ptr, 
                                      WCHAR** data, DWORD *len,
                                      MSIRECORD* record)
{
    FORMAT format;
    FORMSTR *str = NULL;
    STACK *stack, *temp;
    FORMSTR *node;
    int type;

    if (!ptr)
    {
        *data = NULL;
        *len = 0;
        return ERROR_SUCCESS;
    }

    *data = strdupW(ptr);
    *len = lstrlenW(ptr);

    ZeroMemory(&format, sizeof(FORMAT));
    format.package = package;
    format.record = record;
    format.deformatted = *data;
    format.len = *len;

    if (!verify_format(*data))
        return ERROR_SUCCESS;

    stack = create_stack();
    temp = create_stack();

    while ((type = format_lex(&format, &str)) != FORMAT_NULL)
    {
        if (type == FORMAT_LBRACK || type == FORMAT_LBRACE ||
            type == FORMAT_LITERAL || type == FORMAT_NUMBER ||
            type == FORMAT_ESCAPE || type == FORMAT_PROPNULL)
        {
            if (type == FORMAT_LBRACE)
            {
                format.propfailed = FALSE;
                format.groups++;
            }
            else if (type == FORMAT_ESCAPE &&
                     !stack_find(stack, FORMAT_LBRACK))
            {
                format.n -= str->len - 1;
                str->len = 1;
            }

            stack_push(stack, str);
        }
        else if (type == FORMAT_RBRACK || type == FORMAT_RBRACE)
        {
            if (type == FORMAT_RBRACE)
                format.groups--;

            stack_push(stack, str);

            if (stack_find(stack, left_type(type)))
            {
                do
                {
                    node = stack_pop(stack);
                    stack_push(temp, node);
                } while (node->type != left_type(type));

                replace_stack(&format, stack, temp);
            }
        }
    }

    *data = format.deformatted;
    *len = format.len;

    msi_free(str);
    free_stack(stack);
    free_stack(temp);

    return ERROR_SUCCESS;
}

UINT MSI_FormatRecordW( MSIPACKAGE* package, MSIRECORD* record, LPWSTR buffer,
                        LPDWORD size )
{
    WCHAR *format, *deformated = NULL;
    UINT rc = ERROR_INVALID_PARAMETER;
    DWORD len;
    MSIRECORD *record_deformated;
    int field_count, i;

    TRACE("%p %p %p %p\n", package, record, buffer, size);
    dump_record(record);

    if (!(format = msi_dup_record_field( record, 0 )))
        format = build_default_format( record );

    field_count = MSI_RecordGetFieldCount(record);
    record_deformated = MSI_CloneRecord(record);
    if (!record_deformated)
    {
        rc = ERROR_OUTOFMEMORY;
        goto end;
    }
    MSI_RecordSetStringW(record_deformated, 0, format);
    for (i = 1; i <= field_count; i++)
    {
        if (MSI_RecordGetString(record, i))
        {
            deformat_string_internal(package, MSI_RecordGetString(record, i), &deformated, &len, NULL);
            MSI_RecordSetStringW(record_deformated, i, deformated);
            msi_free(deformated);
        }
    }

    deformat_string_internal(package, format, &deformated, &len, record_deformated);
    if (buffer)
    {
        if (*size>len)
        {
            memcpy(buffer,deformated,len*sizeof(WCHAR));
            rc = ERROR_SUCCESS;
            buffer[len] = 0;
        }
        else
        {
            if (*size > 0)
            {
                memcpy(buffer,deformated,(*size)*sizeof(WCHAR));
                buffer[(*size)-1] = 0;
            }
            rc = ERROR_MORE_DATA;
        }
    }
    else rc = ERROR_SUCCESS;

    *size = len;
    msiobj_release(&record_deformated->hdr);
end:
    msi_free( format );
    msi_free( deformated );
    return rc;
}

UINT WINAPI MsiFormatRecordW( MSIHANDLE hInstall, MSIHANDLE hRecord, 
                              LPWSTR szResult, LPDWORD sz )
{
    UINT r = ERROR_INVALID_HANDLE;
    MSIPACKAGE *package;
    MSIRECORD *record;

    TRACE("%d %d %p %p\n", hInstall, hRecord, szResult, sz);

    package = msihandle2msiinfo( hInstall, MSIHANDLETYPE_PACKAGE );
    if (!package)
    {
        HRESULT hr;
        IWineMsiRemotePackage *remote_package;
        BSTR value = NULL;
        awstring wstr;

        remote_package = (IWineMsiRemotePackage *)msi_get_remote( hInstall );
        if (remote_package)
        {
            hr = IWineMsiRemotePackage_FormatRecord( remote_package, hRecord,
                                                     &value );
            if (FAILED(hr))
                goto done;

            wstr.unicode = TRUE;
            wstr.str.w = szResult;
            r = msi_strcpy_to_awstring( value, SysStringLen(value), &wstr, sz );

done:
            IWineMsiRemotePackage_Release( remote_package );
            SysFreeString( value );

            if (FAILED(hr))
            {
                if (HRESULT_FACILITY(hr) == FACILITY_WIN32)
                    return HRESULT_CODE(hr);

                return ERROR_FUNCTION_FAILED;
            }

            return r;
        }
    }

    record = msihandle2msiinfo( hRecord, MSIHANDLETYPE_RECORD );

    if (!record)
        return ERROR_INVALID_HANDLE;
    if (!sz)
    {
        msiobj_release( &record->hdr );
        if (szResult)
            return ERROR_INVALID_PARAMETER;
        else
            return ERROR_SUCCESS;
    }

    r = MSI_FormatRecordW( package, record, szResult, sz );
    msiobj_release( &record->hdr );
    if (package)
        msiobj_release( &package->hdr );
    return r;
}

UINT WINAPI MsiFormatRecordA( MSIHANDLE hInstall, MSIHANDLE hRecord,
                              LPSTR szResult, LPDWORD sz )
{
    UINT r;
    DWORD len, save;
    LPWSTR value;

    TRACE("%d %d %p %p\n", hInstall, hRecord, szResult, sz);

    if (!hRecord)
        return ERROR_INVALID_HANDLE;

    if (!sz)
    {
        if (szResult)
            return ERROR_INVALID_PARAMETER;
        else
            return ERROR_SUCCESS;
    }

    r = MsiFormatRecordW( hInstall, hRecord, NULL, &len );
    if (r != ERROR_SUCCESS)
        return r;

    value = msi_alloc(++len * sizeof(WCHAR));
    if (!value)
        return ERROR_OUTOFMEMORY;

    r = MsiFormatRecordW( hInstall, hRecord, value, &len );
    if (r != ERROR_SUCCESS)
        goto done;

    save = len + 1;
    len = WideCharToMultiByte(CP_ACP, 0, value, len + 1, NULL, 0, NULL, NULL);
    WideCharToMultiByte(CP_ACP, 0, value, len, szResult, *sz, NULL, NULL);

    if (szResult && len > *sz)
    {
        if (*sz) szResult[*sz - 1] = '\0';
        r = ERROR_MORE_DATA;
    }

    *sz = save - 1;

done:
    msi_free(value);
    return r;
}

/* wrapper to resist a need for a full rewrite right now */
DWORD deformat_string( MSIPACKAGE *package, const WCHAR *fmt, WCHAR **data )
{
    DWORD len;
    MSIRECORD *rec;

    *data = NULL;
    if (!fmt) return 0;
    if (!(rec = MSI_CreateRecord( 1 ))) return 0;

    MSI_RecordSetStringW( rec, 0, fmt );
    MSI_FormatRecordW( package, rec, NULL, &len );
    if (!(*data = msi_alloc( ++len * sizeof(WCHAR) )))
    {
        msiobj_release( &rec->hdr );
        return 0;
    }
    MSI_FormatRecordW( package, rec, *data, &len );
    msiobj_release( &rec->hdr );
    return len;
}