diff options
Diffstat (limited to 'src/backend/libpq/pqcomm.c')
| -rw-r--r-- | src/backend/libpq/pqcomm.c | 178 |
1 files changed, 126 insertions, 52 deletions
diff --git a/src/backend/libpq/pqcomm.c b/src/backend/libpq/pqcomm.c index 8f9c14fee9f..386643fe95c 100644 --- a/src/backend/libpq/pqcomm.c +++ b/src/backend/libpq/pqcomm.c @@ -5,39 +5,40 @@ * * Copyright (c) 1994, Regents of the University of California * - * $Id: pqcomm.c,v 1.63 1999/01/17 06:18:26 momjian Exp $ + * $Id: pqcomm.c,v 1.64 1999/01/23 22:27:28 tgl Exp $ * *------------------------------------------------------------------------- */ /* * INTERFACE ROUTINES - * pq_init - initialize libpq + * pq_init - initialize libpq * pq_getport - return the PGPORT setting * pq_close - close input / output connections * pq_flush - flush pending output + * pq_recvbuf - load some bytes into the input buffer * pq_getstr - get a null terminated string from connection - * pq_getchar - get 1 character from connection - * pq_peekchar - peek at first character in connection + * pq_getchar - get 1 character from connection + * pq_peekchar - peek at next character from connection * pq_getnchar - get n characters from connection, and null-terminate * pq_getint - get an integer from connection - * pq_putchar - send 1 character to connection + * pq_putchar - send 1 character to connection * pq_putstr - send a null terminated string to connection * pq_putnchar - send n characters to connection * pq_putint - send an integer to connection - * pq_putncharlen - send n characters to connection + * pq_putncharlen - send n characters to connection * (also send an int header indicating * the length) * pq_getinaddr - initialize address from host and port number * pq_getinserv - initialize address from host and service name * - * StreamDoUnlink - Shutdown UNIX socket connectioin - * StreamServerPort - Open sock stream - * StreamConnection - Create new connection with client - * StreamClose - Close a client/backend connection + * StreamDoUnlink - Shutdown UNIX socket connection + * StreamServerPort - Open socket stream + * StreamConnection - Create new connection with client + * StreamClose - Close a client/backend connection * * NOTES - * Frontend is now completey in interfaces/libpq, and no - * functions from this file is used. + * Frontend is now completely in interfaces/libpq, and no + * functions from this file are used there. * */ #include "postgres.h" @@ -79,6 +80,14 @@ extern FILE * debug_port; /* in util.c */ +/* + * Buffers + */ +char PqSendBuffer[PQ_BUFFER_SIZE]; +char PqRecvBuffer[PQ_BUFFER_SIZE]; +int PqSendPointer,PqRecvPointer,PqRecvLength; + + /* -------------------------------- * pq_init - open portal file descriptors * -------------------------------- @@ -86,6 +95,7 @@ extern FILE * debug_port; /* in util.c */ void pq_init(int fd) { + PqSendPointer = PqRecvPointer = PqRecvLength = 0; PQnotifies_init(); if (getenv("LIBPQ_DEBUG")) debug_port = stderr; @@ -94,40 +104,40 @@ pq_init(int fd) /* ------------------------- * pq_getchar() * - * get a character from the input file, - * + * get a character from the input file, or EOF if trouble + * -------------------------------- */ int pq_getchar(void) { - char c; - - while (recv(MyProcPort->sock, &c, 1, 0) != 1) { - if (errno != EINTR) - return EOF; /* Not interrupted, so something went wrong */ + while (PqRecvPointer >= PqRecvLength) + { + if (pq_recvbuf()) /* If nothing in buffer, then recv some */ + return EOF; /* Failed to recv data */ } - - return c; + return PqRecvBuffer[PqRecvPointer++]; } -/* +/* ------------------------- + * pq_peekchar() + * + * get a character from the connection, but leave it in the buffer + * to be read again * -------------------------------- - * pq_peekchar - get 1 character from connection, but leave it in the stream */ -int -pq_peekchar(void) { - char c; - while (recv(MyProcPort->sock, &c, 1, MSG_PEEK) != 1) { - if (errno != EINTR) - return EOF; /* Not interrupted, so something went wrong */ +int +pq_peekchar(void) +{ + while (PqRecvPointer >= PqRecvLength) + { + if (pq_recvbuf()) /* If nothing in buffer, then recv some */ + return EOF; /* Failed to recv data */ } - - return c; + /* Note we don't bump the pointer... */ + return PqRecvBuffer[PqRecvPointer]; } - - /* -------------------------------- * pq_getport - return the PGPORT setting @@ -150,18 +160,91 @@ pq_getport() void pq_close() { - close(MyProcPort->sock); + close(MyProcPort->sock); PQnotifies_init(); } /* -------------------------------- * pq_flush - flush pending output + * + * returns 0 if OK, EOF if trouble * -------------------------------- */ -void +int pq_flush() { - /* Not supported/required? */ + char *bufptr = PqSendBuffer; + char *bufend = PqSendBuffer + PqSendPointer; + + while (bufptr < bufend) + { + int r = send(MyProcPort->sock, bufptr, bufend - bufptr, 0); + if (r <= 0) + { + if (errno == EINTR) + continue; /* Ok if we were interrupted */ + /* We would like to use elog() here, but cannot because elog + * tries to write to the client, which would cause a recursive + * flush attempt! So just write it out to the postmaster log. + */ + fprintf(stderr, "pq_flush: send() failed, errno %d\n", errno); + /* We drop the buffered data anyway so that processing + * can continue, even though we'll probably quit soon. + */ + PqSendPointer = 0; + return EOF; + } + bufptr += r; + } + PqSendPointer = 0; + return 0; +} + +/* -------------------------------- + * pq_recvbuf - load some bytes into the input buffer + * + * returns 0 if OK, EOF if trouble + * -------------------------------- + */ + +int +pq_recvbuf() +{ + if (PqRecvPointer > 0) + { + if (PqRecvLength > PqRecvPointer) + { + /* still some unread data, left-justify it in the buffer */ + memmove(PqRecvBuffer, PqRecvBuffer+PqRecvPointer, + PqRecvLength-PqRecvPointer); + PqRecvLength -= PqRecvPointer; + PqRecvPointer = 0; + } + else + PqRecvLength = PqRecvPointer = 0; + } + + /* Can fill buffer from PqRecvLength and upwards */ + for (;;) + { + int r = recv(MyProcPort->sock, PqRecvBuffer + PqRecvLength, + PQ_BUFFER_SIZE - PqRecvLength, 0); + if (r <= 0) + { + if (errno == EINTR) + continue; /* Ok if interrupted */ + /* We would like to use elog() here, but dare not because elog + * tries to write to the client, which will cause problems + * if we have a hard communications failure ... + * So just write the message to the postmaster log. + */ + fprintf(stderr, "pq_recvbuf: recv() failed, errno %d\n", errno); + return EOF; + } + /* r contains number of bytes read, so just incr length */ + PqRecvLength += r; + return 0; + } } /* -------------------------------- @@ -194,7 +277,7 @@ pq_getstr(char *s, int maxlen) int pq_getnchar(char *s, int off, int maxlen) { - int r = pqGetNBytes(s + off, maxlen); + int r = pqGetNBytes(s + off, maxlen); s[off+maxlen] = '\0'; return r; } @@ -602,7 +685,7 @@ StreamConnection(int server_fd, Port *port) if (setsockopt(port->sock, pe->p_proto, TCP_NODELAY, &on, sizeof(on)) < 0) { - elog(ERROR, "postmaster: setsockopt failed"); + elog(ERROR, "postmaster: setsockopt failed: %m"); return STATUS_ERROR; } } @@ -644,18 +727,9 @@ pq_putncharlen(char *s, int n) */ int pq_putchar(char c) { - char isDone = 0; - - do { - if (send(MyProcPort->sock, &c, 1, 0) != 1) { - if (errno != EINTR) - return EOF; /* Anything other than interrupt is error! */ - } - else - isDone = 1; /* Done if we sent one char */ - } while (!isDone); - return c; + if (PqSendPointer >= PQ_BUFFER_SIZE) + if (pq_flush()) /* If buffer is full, then flush it out */ + return EOF; + PqSendBuffer[PqSendPointer++] = c; /* Put in buffer */ + return c; } - - - |