fcgiapp.c

FastCGI,语言无关的、可伸缩架构的CGI开放扩展

  ErrorReturn:
    streamCount = -1;
  NormalReturn:
    if(auxBuffPtr != NULL) free(auxBuffPtr);
    return streamCount;
}

/*
 * Copy n characters from *srcPtr to *destPtr, then increment
 * both *srcPtr and *destPtr by n.
 */
static void CopyAndAdvance(char **destPtr, char **srcPtr, int n)
{
    char *dest = *destPtr;
    char *src = *srcPtr;
    int i;
    for (i = 0; i < n; i++)
        *dest++ = *src++;
    *destPtr = dest;
    *srcPtr = src;
}

/*
 *----------------------------------------------------------------------
 *
 * FCGX_FFlush --
 *
 *      Flushes any buffered output.
 *
 *      Server-push is a legitimate application of FCGX_FFlush.
 *      Otherwise, FCGX_FFlush is not very useful, since FCGX_Accept
 *      does it implicitly.  FCGX_FFlush may reduce performance
 *      by increasing the total number of operating system calls
 *      the application makes.
 *
 * Results:
 *      EOF (-1) if an error occurred.
 *
 *----------------------------------------------------------------------
 */
int FCGX_FFlush(FCGX_Stream *stream)
{
    if(stream->isClosed || stream->isReader)
        return 0;
    stream->emptyBuffProc(stream, FALSE);
    return (stream->isClosed) ? -1 : 0;
}

/*
 *----------------------------------------------------------------------
 *
 * FCGX_FClose --
 *
 *      Performs FCGX_FFlush and closes the stream.
 *
 *      This is not a very useful operation, since FCGX_Accept
 *      does it implicitly.  Closing the out stream before the
 *      err stream results in an extra write if there's nothing
 *      in the err stream, and therefore reduces performance.
 *
 * Results:
 *      EOF (-1) if an error occurred.
 *
 *----------------------------------------------------------------------
 */
int FCGX_FClose(FCGX_Stream *stream)
{
    if (stream == NULL) return 0;

    if(!stream->wasFCloseCalled) {
        if(!stream->isReader) {
            stream->emptyBuffProc(stream, TRUE);
        }
        stream->wasFCloseCalled = TRUE;
        stream->isClosed = TRUE;
        if(stream->isReader) {
            stream->wrNext = stream->stop = stream->rdNext;
        } else {
            stream->rdNext = stream->stop = stream->wrNext;
        }
    }
    return (stream->FCGI_errno == 0) ? 0 : EOF;
}

/*
 *----------------------------------------------------------------------
 *
 * SetError --
 *
 *      An error has occurred; save the error code in the stream
 *      for diagnostic purposes and set the stream state so that
 *      reads return EOF and writes have no effect.
 *
 *----------------------------------------------------------------------
 */
static void SetError(FCGX_Stream *stream, int FCGI_errno)
{
    /*
     * Preserve only the first error.
     */
    if(stream->FCGI_errno == 0) {
        stream->FCGI_errno = FCGI_errno;
    }
  
    stream->isClosed = TRUE;
}

/*
 *----------------------------------------------------------------------
 *
 * FCGX_GetError --
 *
 *      Return the stream error code.  0 means no error, > 0
 *      is an errno(2) error, < 0 is an FCGX_errno error.
 *
 *----------------------------------------------------------------------
 */
int FCGX_GetError(FCGX_Stream *stream) {
    return stream->FCGI_errno;
}

/*
 *----------------------------------------------------------------------
 *
 * FCGX_ClearError --
 *
 *      Clear the stream error code and end-of-file indication.
 *
 *----------------------------------------------------------------------
 */
void FCGX_ClearError(FCGX_Stream *stream) {
    stream->FCGI_errno = 0;
    /*
     * stream->isClosed = FALSE;
     * XXX: should clear isClosed but work is needed to make it safe
     * to do so.  For example, if an application calls FClose, gets
     * an I/O error on the write, calls ClearError and retries
     * the FClose, FClose (really EmptyBuffProc) will write a second
     * EOF record.  If an application calls PutChar instead of FClose
     * after the ClearError, the application will write more data.
     * The stream's state must discriminate between various states
     * of the stream that are now all lumped under isClosed.
     */
}

/*
 *======================================================================
 * Parameters
 *======================================================================
 */

/*
 * A vector of pointers representing the parameters received
 * by a FastCGI application server, with the vector's length
 * and last valid element so adding new parameters is efficient.
 */

typedef struct Params {
    FCGX_ParamArray vec;    /* vector of strings */
    int length;		    /* number of string vec can hold */
    char **cur;		    /* current item in vec; *cur == NULL */
} Params;
typedef Params *ParamsPtr;

/*
 *----------------------------------------------------------------------
 *
 * NewParams --
 *
 *	Creates a new Params structure.
 *
 * Results:
 *      Pointer to the new structure.
 *
 *----------------------------------------------------------------------
 */
static ParamsPtr NewParams(int length)
{
    ParamsPtr result;
    result = (Params *)Malloc(sizeof(Params));
    result->vec = (char **)Malloc(length * sizeof(char *));
    result->length = length;
    result->cur = result->vec;
    *result->cur = NULL;
    return result;
}

/*
 *----------------------------------------------------------------------
 *
 * FreeParams --
 *
 *	Frees a Params structure and all the parameters it contains.
 *
 * Side effects:
 *      env becomes invalid.
 *
 *----------------------------------------------------------------------
 */
static void FreeParams(ParamsPtr *paramsPtrPtr)
{
    ParamsPtr paramsPtr = *paramsPtrPtr;
    char **p;
    if(paramsPtr == NULL) {
        return;
    }
    for (p = paramsPtr->vec; p < paramsPtr->cur; p++) {
        free(*p);
    }
    free(paramsPtr->vec);
    free(paramsPtr);
    *paramsPtrPtr = NULL;
}

/*
 *----------------------------------------------------------------------
 *
 * PutParam --
 *
 *	Add a name/value pair to a Params structure.
 *
 * Results:
 *      None.
 *
 * Side effects:
 *      Parameters structure updated.
 *
 *----------------------------------------------------------------------
 */
static void PutParam(ParamsPtr paramsPtr, char *nameValue)
{
    int size;

    *paramsPtr->cur++ = nameValue;
    size = paramsPtr->cur - paramsPtr->vec;
    if(size >= paramsPtr->length) {
	paramsPtr->length *= 2;
	paramsPtr->vec = (FCGX_ParamArray)realloc(paramsPtr->vec, paramsPtr->length * sizeof(char *));
	paramsPtr->cur = paramsPtr->vec + size;
    }
    *paramsPtr->cur = NULL;
}

/*
 *----------------------------------------------------------------------
 *
 * FCGX_GetParam -- obtain value of FCGI parameter in environment
 *
 *
 * Results:
 *	Value bound to name, NULL if name not present in the
 *      environment envp.  Caller must not mutate the result
 *      or retain it past the end of this request.
 *
 *----------------------------------------------------------------------
 */
char *FCGX_GetParam(const char *name, FCGX_ParamArray envp)
{
    int len;
    char **p;

	if (name == NULL || envp == NULL) return NULL;

    len = strlen(name);

    for (p = envp; *p; ++p) {
        if((strncmp(name, *p, len) == 0) && ((*p)[len] == '=')) {
            return *p+len+1;
        }
    }
    return NULL;
}

/*
 *----------------------------------------------------------------------
 *
 * Start of FastCGI-specific code
 *
 *----------------------------------------------------------------------
 */

/*
 *----------------------------------------------------------------------
 *
 * ReadParams --
 *
 *      Reads FastCGI name-value pairs from stream until EOF.  Converts
 *      each pair to name=value format and adds it to Params structure.
 *
 *----------------------------------------------------------------------
 */
static int ReadParams(Params *paramsPtr, FCGX_Stream *stream)
{
    int nameLen, valueLen;
    unsigned char lenBuff[3];
    char *nameValue;

    while((nameLen = FCGX_GetChar(stream)) != EOF) {
        /*
         * Read name length (one or four bytes) and value length
         * (one or four bytes) from stream.
         */
        if((nameLen & 0x80) != 0) {
            if(FCGX_GetStr((char *) &lenBuff[0], 3, stream) != 3) {
                SetError(stream, FCGX_PARAMS_ERROR);
                return -1;
	    }
            nameLen = ((nameLen & 0x7f) << 24) + (lenBuff[0] << 16)
                    + (lenBuff[1] << 8) + lenBuff[2];
        }
        if((valueLen = FCGX_GetChar(stream)) == EOF) {
            SetError(stream, FCGX_PARAMS_ERROR);
            return -1;
	}
        if((valueLen & 0x80) != 0) {
            if(FCGX_GetStr((char *) &lenBuff[0], 3, stream) != 3) {
                SetError(stream, FCGX_PARAMS_ERROR);
                return -1;
	    }
            valueLen = ((valueLen & 0x7f) << 24) + (lenBuff[0] << 16)
                    + (lenBuff[1] << 8) + lenBuff[2];
        }
        /*
         * nameLen and valueLen are now valid; read the name and value
         * from stream and construct a standard environment entry.
         */
        nameValue = (char *)Malloc(nameLen + valueLen + 2);
        if(FCGX_GetStr(nameValue, nameLen, stream) != nameLen) {
            SetError(stream, FCGX_PARAMS_ERROR);
            free(nameValue);
            return -1;
	}
        *(nameValue + nameLen) = '=';
        if(FCGX_GetStr(nameValue + nameLen + 1, valueLen, stream)
                != valueLen) {
            SetError(stream, FCGX_PARAMS_ERROR);
            free(nameValue);
            return -1;
	}
        *(nameValue + nameLen + valueLen + 1) = '\0';
        PutParam(paramsPtr, nameValue);
    }
    return 0;
}

/*
 *----------------------------------------------------------------------
 *
 * MakeHeader --
 *
 *      Constructs an FCGI_Header struct.
 *
 *----------------------------------------------------------------------
 */
static FCGI_Header MakeHeader(
        int type,
        int requestId,
        int contentLength,
        int paddingLength)
{
    FCGI_Header header;
    ASSERT(contentLength >= 0 && contentLength <= FCGI_MAX_LENGTH);
    ASSERT(paddingLength >= 0 && paddingLength <= 0xff);
    header.version = FCGI_VERSION_1;
    header.type             = (unsigned char) type;
    header.requestIdB1      = (unsigned char) ((requestId     >> 8) & 0xff);
    header.requestIdB0      = (unsigned char) ((requestId         ) & 0xff);
    header.contentLengthB1  = (unsigned char) ((contentLength >> 8) & 0xff);
    header.contentLengthB0  = (unsigned char) ((contentLength     ) & 0xff);
    header.paddingLength    = (unsigned char) paddingLength;
    header.reserved         =  0;
    return header;
}

/*
 *----------------------------------------------------------------------
 *
 * MakeEndRequestBody --
 *
 *      Constructs an FCGI_EndRequestBody struct.
 *
 *----------------------------------------------------------------------
 */
static FCGI_EndRequestBody MakeEndRequestBody(
        int appStatus,
        int protocolStatus)
{
    FCGI_EndRequestBody body;
    body.appStatusB3    = (unsigned char) ((appStatus >> 24) & 0xff);
    body.appStatusB2    = (unsigned char) ((appStatus >> 16) & 0xff);
    body.appStatusB1    = (unsigned char) ((appStatus >>  8) & 0xff);
    body.appStatusB0    = (unsigned char) ((appStatus      ) & 0xff);
    body.protocolStatus = (unsigned char) protocolStatus;
    memset(body.reserved, 0, sizeof(body.reserved));
    return body;
}

/*
 *----------------------------------------------------------------------
 *
 * MakeUnknownTypeBody --
 *
 *      Constructs an FCGI_MakeUnknownTypeBody struct.
 *
 *----------------------------------------------------------------------
 */
static FCGI_UnknownTypeBody MakeUnknownTypeBody(
        int type)
{
    FCGI_UnknownTypeBody body;
    body.type = (unsigned char) type;
    memset(body.reserved, 0, sizeof(body.reserved));
    return body;
}

/*
 *----------------------------------------------------------------------
 *
 * AlignInt8 --
 *
 *      Returns the smallest integer greater than or equal to n
 *      that's a multiple of 8.
 *