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-rw-r--r--libpq/fe-misc.c1267
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diff --git a/libpq/fe-misc.c b/libpq/fe-misc.c
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--- a/libpq/fe-misc.c
+++ /dev/null
@@ -1,1267 +0,0 @@
-/*-------------------------------------------------------------------------
- *
- * FILE
- * fe-misc.c
- *
- * DESCRIPTION
- * miscellaneous useful functions
- *
- * The communication routines here are analogous to the ones in
- * backend/libpq/pqcomm.c and backend/libpq/pqcomprim.c, but operate
- * in the considerably different environment of the frontend libpq.
- * In particular, we work with a bare nonblock-mode socket, rather than
- * a stdio stream, so that we can avoid unwanted blocking of the application.
- *
- * XXX: MOVE DEBUG PRINTOUT TO HIGHER LEVEL. As is, block and restart
- * will cause repeat printouts.
- *
- * We must speak the same transmitted data representations as the backend
- * routines.
- *
- *
- * Portions Copyright (c) 1996-2016, PostgreSQL Global Development Group
- * Portions Copyright (c) 1994, Regents of the University of California
- *
- * IDENTIFICATION
- * src/interfaces/libpq/fe-misc.c
- *
- *-------------------------------------------------------------------------
- */
-
-#include "postgres_fe.h"
-
-#include <signal.h>
-#include <time.h>
-
-#include <netinet/in.h>
-#include <arpa/inet.h>
-
-#ifdef WIN32
-#include "win32.h"
-#else
-#include <unistd.h>
-#include <sys/time.h>
-#endif
-
-#ifdef HAVE_POLL_H
-#include <poll.h>
-#endif
-#ifdef HAVE_SYS_POLL_H
-#include <sys/poll.h>
-#endif
-#ifdef HAVE_SYS_SELECT_H
-#include <sys/select.h>
-#endif
-
-#include "libpq-fe.h"
-#include "libpq-int.h"
-#include "mb/pg_wchar.h"
-#include "pg_config_paths.h"
-
-
-static int pqPutMsgBytes(const void *buf, size_t len, PGconn *conn);
-static int pqSendSome(PGconn *conn, int len);
-static int pqSocketCheck(PGconn *conn, int forRead, int forWrite,
- time_t end_time);
-static int pqSocketPoll(int sock, int forRead, int forWrite, time_t end_time);
-
-/*
- * PQlibVersion: return the libpq version number
- */
-int
-PQlibVersion(void)
-{
- return PG_VERSION_NUM;
-}
-
-/*
- * fputnbytes: print exactly N bytes to a file
- *
- * We avoid using %.*s here because it can misbehave if the data
- * is not valid in what libc thinks is the prevailing encoding.
- */
-static void
-fputnbytes(FILE *f, const char *str, size_t n)
-{
- while (n-- > 0)
- fputc(*str++, f);
-}
-
-
-/*
- * pqGetc: get 1 character from the connection
- *
- * All these routines return 0 on success, EOF on error.
- * Note that for the Get routines, EOF only means there is not enough
- * data in the buffer, not that there is necessarily a hard error.
- */
-int
-pqGetc(char *result, PGconn *conn)
-{
- if (conn->inCursor >= conn->inEnd)
- return EOF;
-
- *result = conn->inBuffer[conn->inCursor++];
-
- if (conn->Pfdebug)
- fprintf(conn->Pfdebug, "From backend> %c\n", *result);
-
- return 0;
-}
-
-
-/*
- * pqPutc: write 1 char to the current message
- */
-int
-pqPutc(char c, PGconn *conn)
-{
- if (pqPutMsgBytes(&c, 1, conn))
- return EOF;
-
- if (conn->Pfdebug)
- fprintf(conn->Pfdebug, "To backend> %c\n", c);
-
- return 0;
-}
-
-
-/*
- * pqGets[_append]:
- * get a null-terminated string from the connection,
- * and store it in an expansible PQExpBuffer.
- * If we run out of memory, all of the string is still read,
- * but the excess characters are silently discarded.
- */
-static int
-pqGets_internal(PQExpBuffer buf, PGconn *conn, bool resetbuffer)
-{
- /* Copy conn data to locals for faster search loop */
- char *inBuffer = conn->inBuffer;
- int inCursor = conn->inCursor;
- int inEnd = conn->inEnd;
- int slen;
-
- while (inCursor < inEnd && inBuffer[inCursor])
- inCursor++;
-
- if (inCursor >= inEnd)
- return EOF;
-
- slen = inCursor - conn->inCursor;
-
- if (resetbuffer)
- resetPQExpBuffer(buf);
-
- appendBinaryPQExpBuffer(buf, inBuffer + conn->inCursor, slen);
-
- conn->inCursor = ++inCursor;
-
- if (conn->Pfdebug)
- fprintf(conn->Pfdebug, "From backend> \"%s\"\n",
- buf->data);
-
- return 0;
-}
-
-int
-pqGets(PQExpBuffer buf, PGconn *conn)
-{
- return pqGets_internal(buf, conn, true);
-}
-
-int
-pqGets_append(PQExpBuffer buf, PGconn *conn)
-{
- return pqGets_internal(buf, conn, false);
-}
-
-
-/*
- * pqPuts: write a null-terminated string to the current message
- */
-int
-pqPuts(const char *s, PGconn *conn)
-{
- if (pqPutMsgBytes(s, strlen(s) + 1, conn))
- return EOF;
-
- if (conn->Pfdebug)
- fprintf(conn->Pfdebug, "To backend> \"%s\"\n", s);
-
- return 0;
-}
-
-/*
- * pqGetnchar:
- * get a string of exactly len bytes in buffer s, no null termination
- */
-int
-pqGetnchar(char *s, size_t len, PGconn *conn)
-{
- if (len > (size_t) (conn->inEnd - conn->inCursor))
- return EOF;
-
- memcpy(s, conn->inBuffer + conn->inCursor, len);
- /* no terminating null */
-
- conn->inCursor += len;
-
- if (conn->Pfdebug)
- {
- fprintf(conn->Pfdebug, "From backend (%lu)> ", (unsigned long) len);
- fputnbytes(conn->Pfdebug, s, len);
- fprintf(conn->Pfdebug, "\n");
- }
-
- return 0;
-}
-
-/*
- * pqSkipnchar:
- * skip over len bytes in input buffer.
- *
- * Note: this is primarily useful for its debug output, which should
- * be exactly the same as for pqGetnchar. We assume the data in question
- * will actually be used, but just isn't getting copied anywhere as yet.
- */
-int
-pqSkipnchar(size_t len, PGconn *conn)
-{
- if (len > (size_t) (conn->inEnd - conn->inCursor))
- return EOF;
-
- if (conn->Pfdebug)
- {
- fprintf(conn->Pfdebug, "From backend (%lu)> ", (unsigned long) len);
- fputnbytes(conn->Pfdebug, conn->inBuffer + conn->inCursor, len);
- fprintf(conn->Pfdebug, "\n");
- }
-
- conn->inCursor += len;
-
- return 0;
-}
-
-/*
- * pqPutnchar:
- * write exactly len bytes to the current message
- */
-int
-pqPutnchar(const char *s, size_t len, PGconn *conn)
-{
- if (pqPutMsgBytes(s, len, conn))
- return EOF;
-
- if (conn->Pfdebug)
- {
- fprintf(conn->Pfdebug, "To backend> ");
- fputnbytes(conn->Pfdebug, s, len);
- fprintf(conn->Pfdebug, "\n");
- }
-
- return 0;
-}
-
-/*
- * pqGetInt
- * read a 2 or 4 byte integer and convert from network byte order
- * to local byte order
- */
-int
-pqGetInt(int *result, size_t bytes, PGconn *conn)
-{
- uint16 tmp2;
- uint32 tmp4;
-
- switch (bytes)
- {
- case 2:
- if (conn->inCursor + 2 > conn->inEnd)
- return EOF;
- memcpy(&tmp2, conn->inBuffer + conn->inCursor, 2);
- conn->inCursor += 2;
- *result = (int) ntohs(tmp2);
- break;
- case 4:
- if (conn->inCursor + 4 > conn->inEnd)
- return EOF;
- memcpy(&tmp4, conn->inBuffer + conn->inCursor, 4);
- conn->inCursor += 4;
- *result = (int) ntohl(tmp4);
- break;
- default:
- pqInternalNotice(&conn->noticeHooks,
- "integer of size %lu not supported by pqGetInt",
- (unsigned long) bytes);
- return EOF;
- }
-
- if (conn->Pfdebug)
- fprintf(conn->Pfdebug, "From backend (#%lu)> %d\n", (unsigned long) bytes, *result);
-
- return 0;
-}
-
-/*
- * pqPutInt
- * write an integer of 2 or 4 bytes, converting from host byte order
- * to network byte order.
- */
-int
-pqPutInt(int value, size_t bytes, PGconn *conn)
-{
- uint16 tmp2;
- uint32 tmp4;
-
- switch (bytes)
- {
- case 2:
- tmp2 = htons((uint16) value);
- if (pqPutMsgBytes((const char *) &tmp2, 2, conn))
- return EOF;
- break;
- case 4:
- tmp4 = htonl((uint32) value);
- if (pqPutMsgBytes((const char *) &tmp4, 4, conn))
- return EOF;
- break;
- default:
- pqInternalNotice(&conn->noticeHooks,
- "integer of size %lu not supported by pqPutInt",
- (unsigned long) bytes);
- return EOF;
- }
-
- if (conn->Pfdebug)
- fprintf(conn->Pfdebug, "To backend (%lu#)> %d\n", (unsigned long) bytes, value);
-
- return 0;
-}
-
-/*
- * Make sure conn's output buffer can hold bytes_needed bytes (caller must
- * include already-stored data into the value!)
- *
- * Returns 0 on success, EOF if failed to enlarge buffer
- */
-int
-pqCheckOutBufferSpace(size_t bytes_needed, PGconn *conn)
-{
- int newsize = conn->outBufSize;
- char *newbuf;
-
- /* Quick exit if we have enough space */
- if (bytes_needed <= (size_t) newsize)
- return 0;
-
- /*
- * If we need to enlarge the buffer, we first try to double it in size; if
- * that doesn't work, enlarge in multiples of 8K. This avoids thrashing
- * the malloc pool by repeated small enlargements.
- *
- * Note: tests for newsize > 0 are to catch integer overflow.
- */
- do
- {
- newsize *= 2;
- } while (newsize > 0 && bytes_needed > (size_t) newsize);
-
- if (newsize > 0 && bytes_needed <= (size_t) newsize)
- {
- newbuf = realloc(conn->outBuffer, newsize);
- if (newbuf)
- {
- /* realloc succeeded */
- conn->outBuffer = newbuf;
- conn->outBufSize = newsize;
- return 0;
- }
- }
-
- newsize = conn->outBufSize;
- do
- {
- newsize += 8192;
- } while (newsize > 0 && bytes_needed > (size_t) newsize);
-
- if (newsize > 0 && bytes_needed <= (size_t) newsize)
- {
- newbuf = realloc(conn->outBuffer, newsize);
- if (newbuf)
- {
- /* realloc succeeded */
- conn->outBuffer = newbuf;
- conn->outBufSize = newsize;
- return 0;
- }
- }
-
- /* realloc failed. Probably out of memory */
- printfPQExpBuffer(&conn->errorMessage,
- "cannot allocate memory for output buffer\n");
- return EOF;
-}
-
-/*
- * Make sure conn's input buffer can hold bytes_needed bytes (caller must
- * include already-stored data into the value!)
- *
- * Returns 0 on success, EOF if failed to enlarge buffer
- */
-int
-pqCheckInBufferSpace(size_t bytes_needed, PGconn *conn)
-{
- int newsize = conn->inBufSize;
- char *newbuf;
-
- /* Quick exit if we have enough space */
- if (bytes_needed <= (size_t) newsize)
- return 0;
-
- /*
- * Before concluding that we need to enlarge the buffer, left-justify
- * whatever is in it and recheck. The caller's value of bytes_needed
- * includes any data to the left of inStart, but we can delete that in
- * preference to enlarging the buffer. It's slightly ugly to have this
- * function do this, but it's better than making callers worry about it.
- */
- bytes_needed -= conn->inStart;
-
- if (conn->inStart < conn->inEnd)
- {
- if (conn->inStart > 0)
- {
- memmove(conn->inBuffer, conn->inBuffer + conn->inStart,
- conn->inEnd - conn->inStart);
- conn->inEnd -= conn->inStart;
- conn->inCursor -= conn->inStart;
- conn->inStart = 0;
- }
- }
- else
- {
- /* buffer is logically empty, reset it */
- conn->inStart = conn->inCursor = conn->inEnd = 0;
- }
-
- /* Recheck whether we have enough space */
- if (bytes_needed <= (size_t) newsize)
- return 0;
-
- /*
- * If we need to enlarge the buffer, we first try to double it in size; if
- * that doesn't work, enlarge in multiples of 8K. This avoids thrashing
- * the malloc pool by repeated small enlargements.
- *
- * Note: tests for newsize > 0 are to catch integer overflow.
- */
- do
- {
- newsize *= 2;
- } while (newsize > 0 && bytes_needed > (size_t) newsize);
-
- if (newsize > 0 && bytes_needed <= (size_t) newsize)
- {
- newbuf = realloc(conn->inBuffer, newsize);
- if (newbuf)
- {
- /* realloc succeeded */
- conn->inBuffer = newbuf;
- conn->inBufSize = newsize;
- return 0;
- }
- }
-
- newsize = conn->inBufSize;
- do
- {
- newsize += 8192;
- } while (newsize > 0 && bytes_needed > (size_t) newsize);
-
- if (newsize > 0 && bytes_needed <= (size_t) newsize)
- {
- newbuf = realloc(conn->inBuffer, newsize);
- if (newbuf)
- {
- /* realloc succeeded */
- conn->inBuffer = newbuf;
- conn->inBufSize = newsize;
- return 0;
- }
- }
-
- /* realloc failed. Probably out of memory */
- printfPQExpBuffer(&conn->errorMessage,
- "cannot allocate memory for input buffer\n");
- return EOF;
-}
-
-/*
- * pqPutMsgStart: begin construction of a message to the server
- *
- * msg_type is the message type byte, or 0 for a message without type byte
- * (only startup messages have no type byte)
- *
- * force_len forces the message to have a length word; otherwise, we add
- * a length word if protocol 3.
- *
- * Returns 0 on success, EOF on error
- *
- * The idea here is that we construct the message in conn->outBuffer,
- * beginning just past any data already in outBuffer (ie, at
- * outBuffer+outCount). We enlarge the buffer as needed to hold the message.
- * When the message is complete, we fill in the length word (if needed) and
- * then advance outCount past the message, making it eligible to send.
- *
- * The state variable conn->outMsgStart points to the incomplete message's
- * length word: it is either outCount or outCount+1 depending on whether
- * there is a type byte. If we are sending a message without length word
- * (pre protocol 3.0 only), then outMsgStart is -1. The state variable
- * conn->outMsgEnd is the end of the data collected so far.
- */
-int
-pqPutMsgStart(char msg_type, bool force_len, PGconn *conn)
-{
- int lenPos;
- int endPos;
-
- /* allow room for message type byte */
- if (msg_type)
- endPos = conn->outCount + 1;
- else
- endPos = conn->outCount;
-
- /* do we want a length word? */
- if (force_len || PG_PROTOCOL_MAJOR(conn->pversion) >= 3)
- {
- lenPos = endPos;
- /* allow room for message length */
- endPos += 4;
- }
- else
- lenPos = -1;
-
- /* make sure there is room for message header */
- if (pqCheckOutBufferSpace(endPos, conn))
- return EOF;
- /* okay, save the message type byte if any */
- if (msg_type)
- conn->outBuffer[conn->outCount] = msg_type;
- /* set up the message pointers */
- conn->outMsgStart = lenPos;
- conn->outMsgEnd = endPos;
- /* length word, if needed, will be filled in by pqPutMsgEnd */
-
- if (conn->Pfdebug)
- fprintf(conn->Pfdebug, "To backend> Msg %c\n",
- msg_type ? msg_type : ' ');
-
- return 0;
-}
-
-/*
- * pqPutMsgBytes: add bytes to a partially-constructed message
- *
- * Returns 0 on success, EOF on error
- */
-static int
-pqPutMsgBytes(const void *buf, size_t len, PGconn *conn)
-{
- /* make sure there is room for it */
- if (pqCheckOutBufferSpace(conn->outMsgEnd + len, conn))
- return EOF;
- /* okay, save the data */
- memcpy(conn->outBuffer + conn->outMsgEnd, buf, len);
- conn->outMsgEnd += len;
- /* no Pfdebug call here, caller should do it */
- return 0;
-}
-
-/*
- * pqPutMsgEnd: finish constructing a message and possibly send it
- *
- * Returns 0 on success, EOF on error
- *
- * We don't actually send anything here unless we've accumulated at least
- * 8K worth of data (the typical size of a pipe buffer on Unix systems).
- * This avoids sending small partial packets. The caller must use pqFlush
- * when it's important to flush all the data out to the server.
- */
-int
-pqPutMsgEnd(PGconn *conn)
-{
- if (conn->Pfdebug)
- fprintf(conn->Pfdebug, "To backend> Msg complete, length %u\n",
- conn->outMsgEnd - conn->outCount);
-
- /* Fill in length word if needed */
- if (conn->outMsgStart >= 0)
- {
- uint32 msgLen = conn->outMsgEnd - conn->outMsgStart;
-
- msgLen = htonl(msgLen);
- memcpy(conn->outBuffer + conn->outMsgStart, &msgLen, 4);
- }
-
- /* Make message eligible to send */
- conn->outCount = conn->outMsgEnd;
-
- if (conn->outCount >= 8192)
- {
- int toSend = conn->outCount - (conn->outCount % 8192);
-
- if (pqSendSome(conn, toSend) < 0)
- return EOF;
- /* in nonblock mode, don't complain if unable to send it all */
- }
-
- return 0;
-}
-
-/* ----------
- * pqReadData: read more data, if any is available
- * Possible return values:
- * 1: successfully loaded at least one more byte
- * 0: no data is presently available, but no error detected
- * -1: error detected (including EOF = connection closure);
- * conn->errorMessage set
- * NOTE: callers must not assume that pointers or indexes into conn->inBuffer
- * remain valid across this call!
- * ----------
- */
-int
-pqReadData(PGconn *conn)
-{
- int someread = 0;
- int nread;
-
- if (conn->sock == PGINVALID_SOCKET)
- {
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("connection not open\n"));
- return -1;
- }
-
- /* Left-justify any data in the buffer to make room */
- if (conn->inStart < conn->inEnd)
- {
- if (conn->inStart > 0)
- {
- memmove(conn->inBuffer, conn->inBuffer + conn->inStart,
- conn->inEnd - conn->inStart);
- conn->inEnd -= conn->inStart;
- conn->inCursor -= conn->inStart;
- conn->inStart = 0;
- }
- }
- else
- {
- /* buffer is logically empty, reset it */
- conn->inStart = conn->inCursor = conn->inEnd = 0;
- }
-
- /*
- * If the buffer is fairly full, enlarge it. We need to be able to enlarge
- * the buffer in case a single message exceeds the initial buffer size. We
- * enlarge before filling the buffer entirely so as to avoid asking the
- * kernel for a partial packet. The magic constant here should be large
- * enough for a TCP packet or Unix pipe bufferload. 8K is the usual pipe
- * buffer size, so...
- */
- if (conn->inBufSize - conn->inEnd < 8192)
- {
- if (pqCheckInBufferSpace(conn->inEnd + (size_t) 8192, conn))
- {
- /*
- * We don't insist that the enlarge worked, but we need some room
- */
- if (conn->inBufSize - conn->inEnd < 100)
- return -1; /* errorMessage already set */
- }
- }
-
- /* OK, try to read some data */
-retry3:
- nread = pqsecure_read(conn, conn->inBuffer + conn->inEnd,
- conn->inBufSize - conn->inEnd);
- if (nread < 0)
- {
- if (SOCK_ERRNO == EINTR)
- goto retry3;
- /* Some systems return EAGAIN/EWOULDBLOCK for no data */
-#ifdef EAGAIN
- if (SOCK_ERRNO == EAGAIN)
- return someread;
-#endif
-#if defined(EWOULDBLOCK) && (!defined(EAGAIN) || (EWOULDBLOCK != EAGAIN))
- if (SOCK_ERRNO == EWOULDBLOCK)
- return someread;
-#endif
- /* We might get ECONNRESET here if using TCP and backend died */
-#ifdef ECONNRESET
- if (SOCK_ERRNO == ECONNRESET)
- goto definitelyFailed;
-#endif
- /* pqsecure_read set the error message for us */
- return -1;
- }
- if (nread > 0)
- {
- conn->inEnd += nread;
-
- /*
- * Hack to deal with the fact that some kernels will only give us back
- * 1 packet per recv() call, even if we asked for more and there is
- * more available. If it looks like we are reading a long message,
- * loop back to recv() again immediately, until we run out of data or
- * buffer space. Without this, the block-and-restart behavior of
- * libpq's higher levels leads to O(N^2) performance on long messages.
- *
- * Since we left-justified the data above, conn->inEnd gives the
- * amount of data already read in the current message. We consider
- * the message "long" once we have acquired 32k ...
- */
- if (conn->inEnd > 32768 &&
- (conn->inBufSize - conn->inEnd) >= 8192)
- {
- someread = 1;
- goto retry3;
- }
- return 1;
- }
-
- if (someread)
- return 1; /* got a zero read after successful tries */
-
- /*
- * A return value of 0 could mean just that no data is now available, or
- * it could mean EOF --- that is, the server has closed the connection.
- * Since we have the socket in nonblock mode, the only way to tell the
- * difference is to see if select() is saying that the file is ready.
- * Grumble. Fortunately, we don't expect this path to be taken much,
- * since in normal practice we should not be trying to read data unless
- * the file selected for reading already.
- *
- * In SSL mode it's even worse: SSL_read() could say WANT_READ and then
- * data could arrive before we make the pqReadReady() test, but the second
- * SSL_read() could still say WANT_READ because the data received was not
- * a complete SSL record. So we must play dumb and assume there is more
- * data, relying on the SSL layer to detect true EOF.
- */
-
-#ifdef USE_SSL
- if (conn->ssl_in_use)
- return 0;
-#endif
-
- switch (pqReadReady(conn))
- {
- case 0:
- /* definitely no data available */
- return 0;
- case 1:
- /* ready for read */
- break;
- default:
- /* we override pqReadReady's message with something more useful */
- goto definitelyEOF;
- }
-
- /*
- * Still not sure that it's EOF, because some data could have just
- * arrived.
- */
-retry4:
- nread = pqsecure_read(conn, conn->inBuffer + conn->inEnd,
- conn->inBufSize - conn->inEnd);
- if (nread < 0)
- {
- if (SOCK_ERRNO == EINTR)
- goto retry4;
- /* Some systems return EAGAIN/EWOULDBLOCK for no data */
-#ifdef EAGAIN
- if (SOCK_ERRNO == EAGAIN)
- return 0;
-#endif
-#if defined(EWOULDBLOCK) && (!defined(EAGAIN) || (EWOULDBLOCK != EAGAIN))
- if (SOCK_ERRNO == EWOULDBLOCK)
- return 0;
-#endif
- /* We might get ECONNRESET here if using TCP and backend died */
-#ifdef ECONNRESET
- if (SOCK_ERRNO == ECONNRESET)
- goto definitelyFailed;
-#endif
- /* pqsecure_read set the error message for us */
- return -1;
- }
- if (nread > 0)
- {
- conn->inEnd += nread;
- return 1;
- }
-
- /*
- * OK, we are getting a zero read even though select() says ready. This
- * means the connection has been closed. Cope.
- */
-definitelyEOF:
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext(
- "server closed the connection unexpectedly\n"
- "\tThis probably means the server terminated abnormally\n"
- "\tbefore or while processing the request.\n"));
-
- /* Come here if lower-level code already set a suitable errorMessage */
-definitelyFailed:
- /* Do *not* drop any already-read data; caller still wants it */
- pqDropConnection(conn, false);
- conn->status = CONNECTION_BAD; /* No more connection to backend */
- return -1;
-}
-
-/*
- * pqSendSome: send data waiting in the output buffer.
- *
- * len is how much to try to send (typically equal to outCount, but may
- * be less).
- *
- * Return 0 on success, -1 on failure and 1 when not all data could be sent
- * because the socket would block and the connection is non-blocking.
- */
-static int
-pqSendSome(PGconn *conn, int len)
-{
- char *ptr = conn->outBuffer;
- int remaining = conn->outCount;
- int result = 0;
-
- if (conn->sock == PGINVALID_SOCKET)
- {
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("connection not open\n"));
- /* Discard queued data; no chance it'll ever be sent */
- conn->outCount = 0;
- return -1;
- }
-
- /* while there's still data to send */
- while (len > 0)
- {
- int sent;
-
-#ifndef WIN32
- sent = pqsecure_write(conn, ptr, len);
-#else
-
- /*
- * Windows can fail on large sends, per KB article Q201213. The
- * failure-point appears to be different in different versions of
- * Windows, but 64k should always be safe.
- */
- sent = pqsecure_write(conn, ptr, Min(len, 65536));
-#endif
-
- if (sent < 0)
- {
- /* Anything except EAGAIN/EWOULDBLOCK/EINTR is trouble */
- switch (SOCK_ERRNO)
- {
-#ifdef EAGAIN
- case EAGAIN:
- break;
-#endif
-#if defined(EWOULDBLOCK) && (!defined(EAGAIN) || (EWOULDBLOCK != EAGAIN))
- case EWOULDBLOCK:
- break;
-#endif
- case EINTR:
- continue;
-
- default:
- /* pqsecure_write set the error message for us */
-
- /*
- * We used to close the socket here, but that's a bad idea
- * since there might be unread data waiting (typically, a
- * NOTICE message from the backend telling us it's
- * committing hara-kiri...). Leave the socket open until
- * pqReadData finds no more data can be read. But abandon
- * attempt to send data.
- */
- conn->outCount = 0;
- return -1;
- }
- }
- else
- {
- ptr += sent;
- len -= sent;
- remaining -= sent;
- }
-
- if (len > 0)
- {
- /*
- * We didn't send it all, wait till we can send more.
- *
- * There are scenarios in which we can't send data because the
- * communications channel is full, but we cannot expect the server
- * to clear the channel eventually because it's blocked trying to
- * send data to us. (This can happen when we are sending a large
- * amount of COPY data, and the server has generated lots of
- * NOTICE responses.) To avoid a deadlock situation, we must be
- * prepared to accept and buffer incoming data before we try
- * again. Furthermore, it is possible that such incoming data
- * might not arrive until after we've gone to sleep. Therefore,
- * we wait for either read ready or write ready.
- *
- * In non-blocking mode, we don't wait here directly, but return 1
- * to indicate that data is still pending. The caller should wait
- * for both read and write ready conditions, and call
- * PQconsumeInput() on read ready, but just in case it doesn't, we
- * call pqReadData() ourselves before returning. That's not
- * enough if the data has not arrived yet, but it's the best we
- * can do, and works pretty well in practice. (The documentation
- * used to say that you only need to wait for write-ready, so
- * there are still plenty of applications like that out there.)
- */
- if (pqReadData(conn) < 0)
- {
- result = -1; /* error message already set up */
- break;
- }
-
- if (pqIsnonblocking(conn))
- {
- result = 1;
- break;
- }
-
- if (pqWait(TRUE, TRUE, conn))
- {
- result = -1;
- break;
- }
- }
- }
-
- /* shift the remaining contents of the buffer */
- if (remaining > 0)
- memmove(conn->outBuffer, ptr, remaining);
- conn->outCount = remaining;
-
- return result;
-}
-
-
-/*
- * pqFlush: send any data waiting in the output buffer
- *
- * Return 0 on success, -1 on failure and 1 when not all data could be sent
- * because the socket would block and the connection is non-blocking.
- */
-int
-pqFlush(PGconn *conn)
-{
- if (conn->Pfdebug)
- fflush(conn->Pfdebug);
-
- if (conn->outCount > 0)
- return pqSendSome(conn, conn->outCount);
-
- return 0;
-}
-
-
-/*
- * pqWait: wait until we can read or write the connection socket
- *
- * JAB: If SSL enabled and used and forRead, buffered bytes short-circuit the
- * call to select().
- *
- * We also stop waiting and return if the kernel flags an exception condition
- * on the socket. The actual error condition will be detected and reported
- * when the caller tries to read or write the socket.
- */
-int
-pqWait(int forRead, int forWrite, PGconn *conn)
-{
- return pqWaitTimed(forRead, forWrite, conn, (time_t) -1);
-}
-
-/*
- * pqWaitTimed: wait, but not past finish_time.
- *
- * If finish_time is exceeded then we return failure (EOF). This is like
- * the response for a kernel exception because we don't want the caller
- * to try to read/write in that case.
- *
- * finish_time = ((time_t) -1) disables the wait limit.
- */
-int
-pqWaitTimed(int forRead, int forWrite, PGconn *conn, time_t finish_time)
-{
- int result;
-
- result = pqSocketCheck(conn, forRead, forWrite, finish_time);
-
- if (result < 0)
- return EOF; /* errorMessage is already set */
-
- if (result == 0)
- {
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("timeout expired\n"));
- return EOF;
- }
-
- return 0;
-}
-
-/*
- * pqReadReady: is select() saying the file is ready to read?
- * Returns -1 on failure, 0 if not ready, 1 if ready.
- */
-int
-pqReadReady(PGconn *conn)
-{
- return pqSocketCheck(conn, 1, 0, (time_t) 0);
-}
-
-/*
- * pqWriteReady: is select() saying the file is ready to write?
- * Returns -1 on failure, 0 if not ready, 1 if ready.
- */
-int
-pqWriteReady(PGconn *conn)
-{
- return pqSocketCheck(conn, 0, 1, (time_t) 0);
-}
-
-/*
- * Checks a socket, using poll or select, for data to be read, written,
- * or both. Returns >0 if one or more conditions are met, 0 if it timed
- * out, -1 if an error occurred.
- *
- * If SSL is in use, the SSL buffer is checked prior to checking the socket
- * for read data directly.
- */
-static int
-pqSocketCheck(PGconn *conn, int forRead, int forWrite, time_t end_time)
-{
- int result;
-
- if (!conn)
- return -1;
- if (conn->sock == PGINVALID_SOCKET)
- {
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("invalid socket\n"));
- return -1;
- }
-
-#ifdef USE_SSL
- /* Check for SSL library buffering read bytes */
- if (forRead && conn->ssl_in_use && pgtls_read_pending(conn) > 0)
- {
- /* short-circuit the select */
- return 1;
- }
-#endif
-
- /* We will retry as long as we get EINTR */
- do
- result = pqSocketPoll(conn->sock, forRead, forWrite, end_time);
- while (result < 0 && SOCK_ERRNO == EINTR);
-
- if (result < 0)
- {
- char sebuf[256];
-
- printfPQExpBuffer(&conn->errorMessage,
- libpq_gettext("select() failed: %s\n"),
- SOCK_STRERROR(SOCK_ERRNO, sebuf, sizeof(sebuf)));
- }
-
- return result;
-}
-
-
-/*
- * Check a file descriptor for read and/or write data, possibly waiting.
- * If neither forRead nor forWrite are set, immediately return a timeout
- * condition (without waiting). Return >0 if condition is met, 0
- * if a timeout occurred, -1 if an error or interrupt occurred.
- *
- * Timeout is infinite if end_time is -1. Timeout is immediate (no blocking)
- * if end_time is 0 (or indeed, any time before now).
- */
-static int
-pqSocketPoll(int sock, int forRead, int forWrite, time_t end_time)
-{
- /* We use poll(2) if available, otherwise select(2) */
-#ifdef HAVE_POLL
- struct pollfd input_fd;
- int timeout_ms;
-
- if (!forRead && !forWrite)
- return 0;
-
- input_fd.fd = sock;
- input_fd.events = POLLERR;
- input_fd.revents = 0;
-
- if (forRead)
- input_fd.events |= POLLIN;
- if (forWrite)
- input_fd.events |= POLLOUT;
-
- /* Compute appropriate timeout interval */
- if (end_time == ((time_t) -1))
- timeout_ms = -1;
- else
- {
- time_t now = time(NULL);
-
- if (end_time > now)
- timeout_ms = (end_time - now) * 1000;
- else
- timeout_ms = 0;
- }
-
- return poll(&input_fd, 1, timeout_ms);
-#else /* !HAVE_POLL */
-
- fd_set input_mask;
- fd_set output_mask;
- fd_set except_mask;
- struct timeval timeout;
- struct timeval *ptr_timeout;
-
- if (!forRead && !forWrite)
- return 0;
-
- FD_ZERO(&input_mask);
- FD_ZERO(&output_mask);
- FD_ZERO(&except_mask);
- if (forRead)
- FD_SET(sock, &input_mask);
-
- if (forWrite)
- FD_SET(sock, &output_mask);
- FD_SET(sock, &except_mask);
-
- /* Compute appropriate timeout interval */
- if (end_time == ((time_t) -1))
- ptr_timeout = NULL;
- else
- {
- time_t now = time(NULL);
-
- if (end_time > now)
- timeout.tv_sec = end_time - now;
- else
- timeout.tv_sec = 0;
- timeout.tv_usec = 0;
- ptr_timeout = &timeout;
- }
-
- return select(sock + 1, &input_mask, &output_mask,
- &except_mask, ptr_timeout);
-#endif /* HAVE_POLL */
-}
-
-
-/*
- * A couple of "miscellaneous" multibyte related functions. They used
- * to be in fe-print.c but that file is doomed.
- */
-
-/*
- * returns the byte length of the character beginning at s, using the
- * specified encoding.
- */
-int
-PQmblen(const char *s, int encoding)
-{
- return pg_encoding_mblen(encoding, s);
-}
-
-/*
- * returns the display length of the character beginning at s, using the
- * specified encoding.
- */
-int
-PQdsplen(const char *s, int encoding)
-{
- return pg_encoding_dsplen(encoding, s);
-}
-
-/*
- * Get encoding id from environment variable PGCLIENTENCODING.
- */
-int
-PQenv2encoding(void)
-{
- char *str;
- int encoding = PG_SQL_ASCII;
-
- str = getenv("PGCLIENTENCODING");
- if (str && *str != '\0')
- {
- encoding = pg_char_to_encoding(str);
- if (encoding < 0)
- encoding = PG_SQL_ASCII;
- }
- return encoding;
-}
-
-
-#ifdef ENABLE_NLS
-
-static void
-libpq_binddomain()
-{
- static bool already_bound = false;
-
- if (!already_bound)
- {
- /* bindtextdomain() does not preserve errno */
-#ifdef WIN32
- int save_errno = GetLastError();
-#else
- int save_errno = errno;
-#endif
- const char *ldir;
-
- already_bound = true;
- /* No relocatable lookup here because the binary could be anywhere */
- ldir = getenv("PGLOCALEDIR");
- if (!ldir)
- ldir = LOCALEDIR;
- bindtextdomain(PG_TEXTDOMAIN("libpq"), ldir);
-#ifdef WIN32
- SetLastError(save_errno);
-#else
- errno = save_errno;
-#endif
- }
-}
-
-char *
-libpq_gettext(const char *msgid)
-{
- libpq_binddomain();
- return dgettext(PG_TEXTDOMAIN("libpq"), msgid);
-}
-
-char *
-libpq_ngettext(const char *msgid, const char *msgid_plural, unsigned long n)
-{
- libpq_binddomain();
- return dngettext(PG_TEXTDOMAIN("libpq"), msgid, msgid_plural, n);
-}
-
-#endif /* ENABLE_NLS */
generated by cgit v1.1 at 2024-04-25 07:05:36 +0000