* rework stringbuffered reading on nonblocking files

[citadel.git] / libcitadel / lib / stringbuf.c

diff --git a/libcitadel/lib/stringbuf.c b/libcitadel/lib/stringbuf.c
index 00d935896c561591766c769e41b14ccb81122922..463f978b5e8e44e505e7c969dd4379b05e49da54 100644 (file)
--- a/libcitadel/lib/stringbuf.c
+++ b/libcitadel/lib/stringbuf.c
@@ -1703,6 +1703,7 @@ int StrBufTCP_read_buffered_line(StrBuf *Line,
        fd_set rfds;
        char *pch = NULL;
         int fdflags;
+       int IsNonBlock;
        struct timeval tv;
 
        if (buf->BufUsed > 0) {
@@ -1722,43 +1723,46 @@ int StrBufTCP_read_buffered_line(StrBuf *Line,
                IncreaseBuf(buf, 1, -1);
 
        fdflags = fcntl(*fd, F_GETFL);
-       if ((fdflags & O_NONBLOCK) == O_NONBLOCK)
-               return -1;
+       IsNonBlock = (fdflags & O_NONBLOCK) == O_NONBLOCK;
 
        while ((nSuccessLess < timeout) && (pch == NULL)) {
-               tv.tv_sec = selectresolution;
-               tv.tv_usec = 0;
-               
-               FD_ZERO(&rfds);
-               FD_SET(*fd, &rfds);
-               if (select(*fd + 1, NULL, &rfds, NULL, &tv) == -1) {
-                       *Error = strerror(errno);
-                       close (*fd);
-                       *fd = -1;
-                       return -1;
-               }               
-               if (FD_ISSET(*fd, &rfds)) {
-                       rlen = read(*fd, 
-                                   &buf->buf[buf->BufUsed], 
-                                   buf->BufSize - buf->BufUsed - 1);
-                       if (rlen < 1) {
+               if (IsNonBlock){
+                       tv.tv_sec = selectresolution;
+                       tv.tv_usec = 0;
+                       
+                       FD_ZERO(&rfds);
+                       FD_SET(*fd, &rfds);
+                       if (select(*fd + 1, NULL, &rfds, NULL, &tv) == -1) {
                                *Error = strerror(errno);
-                               close(*fd);
+                               close (*fd);
                                *fd = -1;
                                return -1;
                        }
-                       else if (rlen > 0) {
-                               nSuccessLess = 0;
-                               buf->BufUsed += rlen;
-                               buf->buf[buf->BufUsed] = '\0';
-                               if (buf->BufUsed + 10 > buf->BufSize) {
-                                       IncreaseBuf(buf, 1, -1);
-                               }
-                               pch = strchr(buf->buf, '\n');
-                               continue;
+               }
+               if (IsNonBlock && !  FD_ISSET(*fd, &rfds)) {
+                       nSuccessLess ++;
+                       continue;
+               }
+               rlen = read(*fd, 
+                           &buf->buf[buf->BufUsed], 
+                           buf->BufSize - buf->BufUsed - 1);
+               if (rlen < 1) {
+                       *Error = strerror(errno);
+                       close(*fd);
+                       *fd = -1;
+                       return -1;
+               }
+               else if (rlen > 0) {
+                       nSuccessLess = 0;
+                       buf->BufUsed += rlen;
+                       buf->buf[buf->BufUsed] = '\0';
+                       if (buf->BufUsed + 10 > buf->BufSize) {
+                               IncreaseBuf(buf, 1, -1);
                        }
+                       pch = strchr(buf->buf, '\n');
+                       continue;
                }
-               nSuccessLess ++;
+               
        }
        if (pch != NULL) {
                rlen = 0;
@@ -1773,7 +1777,6 @@ int StrBufTCP_read_buffered_line(StrBuf *Line,
 
 }
 
-static const char *ErrRBLF_WrongFDFlags="StrBufTCP_read_buffered_line_fast: don't work with fdflags & O_NONBLOCK";
 static const char *ErrRBLF_SelectFailed="StrBufTCP_read_buffered_line_fast: Select failed without reason";
 static const char *ErrRBLF_NotEnoughSentFromServer="StrBufTCP_read_buffered_line_fast: No complete line was sent from peer";
 /**
@@ -1801,6 +1804,7 @@ int StrBufTCP_read_buffered_line_fast(StrBuf *Line,
        fd_set rfds;
        const char *pch = NULL;
         int fdflags;
+       int IsNonBlock;
        struct timeval tv;
        
        pos = *Pos;
@@ -1840,54 +1844,55 @@ int StrBufTCP_read_buffered_line_fast(StrBuf *Line,
        }
 
        fdflags = fcntl(*fd, F_GETFL);
-       if ((fdflags & O_NONBLOCK) == O_NONBLOCK) {
-               *Error = ErrRBLF_WrongFDFlags;
-               return -1;
-       }
+       IsNonBlock = (fdflags & O_NONBLOCK) == O_NONBLOCK;
 
        pch = NULL;
        while ((nSuccessLess < timeout) && (pch == NULL)) {
-               tv.tv_sec = selectresolution;
-               tv.tv_usec = 0;
+               if (IsNonBlock)
+               {
+                       tv.tv_sec = 1;
+                       tv.tv_usec = 0;
                
-               FD_ZERO(&rfds);
-               FD_SET(*fd, &rfds);
-               if (select(*fd + 1, NULL, &rfds, NULL, &tv) == -1) {
-                       *Error = strerror(errno);
-                       close (*fd);
-                       *fd = -1;
-                       if (*Error == NULL)
-                               *Error = ErrRBLF_SelectFailed;
-                       return -1;
-               }               
-               if (FD_ISSET(*fd, &rfds) != 0) {
-                       rlen = read(*fd, 
-                                   &IOBuf->buf[IOBuf->BufUsed], 
-                                   IOBuf->BufSize - IOBuf->BufUsed - 1);
-                       if (rlen < 1) {
+                       FD_ZERO(&rfds);
+                       FD_SET(*fd, &rfds);
+                       if (select((*fd) + 1, &rfds, NULL, NULL, &tv) == -1) {
                                *Error = strerror(errno);
-                               close(*fd);
+                               close (*fd);
                                *fd = -1;
+                               if (*Error == NULL)
+                                       *Error = ErrRBLF_SelectFailed;
                                return -1;
                        }
-                       else if (rlen > 0) {
-                               nSuccessLess = 0;
-                               IOBuf->BufUsed += rlen;
-                               IOBuf->buf[IOBuf->BufUsed] = '\0';
-                               if (IOBuf->BufUsed + 10 > IOBuf->BufSize) {
-                                       IncreaseBuf(IOBuf, 1, -1);
-                               }
-
-                               pche = IOBuf->buf + IOBuf->BufUsed;
-                               pch = IOBuf->buf;
-                               while ((pch < pche) && (*pch != '\n'))
-                                       pch ++;
-                               if ((pch >= pche) || (*pch == '\0'))
-                                       pch = NULL;
+                       if (! FD_ISSET(*fd, &rfds) != 0) {
+                               nSuccessLess ++;
                                continue;
                        }
                }
-               nSuccessLess ++;
+               rlen = read(*fd, 
+                           &IOBuf->buf[IOBuf->BufUsed], 
+                           IOBuf->BufSize - IOBuf->BufUsed - 1);
+               if (rlen < 1) {
+                       *Error = strerror(errno);
+                       close(*fd);
+                       *fd = -1;
+                       return -1;
+               }
+               else if (rlen > 0) {
+                       nSuccessLess = 0;
+                       IOBuf->BufUsed += rlen;
+                       IOBuf->buf[IOBuf->BufUsed] = '\0';
+                       if (IOBuf->BufUsed + 10 > IOBuf->BufSize) {
+                               IncreaseBuf(IOBuf, 1, -1);
+                       }
+                       
+                       pche = IOBuf->buf + IOBuf->BufUsed;
+                       pch = IOBuf->buf;
+                       while ((pch < pche) && (*pch != '\n'))
+                               pch ++;
+                       if ((pch >= pche) || (*pch == '\0'))
+                               pch = NULL;
+                       continue;
+               }
        }
        if (pch != NULL) {
                pos = IOBuf->buf;
@@ -1916,12 +1921,14 @@ int StrBufTCP_read_buffered_line_fast(StrBuf *Line,
  */
 int StrBufReadBLOB(StrBuf *Buf, int *fd, int append, long nBytes, const char **Error)
 {
-        fd_set wset;
-        int fdflags;
+       int fdflags;
        int len, rlen, slen;
+       int nSuccessLess;
        int nRead = 0;
        char *ptr;
-
+       int IsNonBlock;
+       struct timeval tv;
+       fd_set rfds;
        if ((Buf == NULL) || (*fd == -1))
                return -1;
        if (!append)
@@ -1934,16 +1941,29 @@ int StrBufReadBLOB(StrBuf *Buf, int *fd, int append, long nBytes, const char **E
        slen = len = Buf->BufUsed;
 
        fdflags = fcntl(*fd, F_GETFL);
-
+       IsNonBlock = (fdflags & O_NONBLOCK) == O_NONBLOCK;
+       nSuccessLess = 0;
        while (nRead < nBytes) {
-               if ((fdflags & O_NONBLOCK) == O_NONBLOCK) {
-                        FD_ZERO(&wset);
-                        FD_SET(*fd, &wset);
-                        if (select(*fd + 1, NULL, &wset, NULL, NULL) == -1) {
+               if (IsNonBlock)
+               {
+                       tv.tv_sec = 1;
+                       tv.tv_usec = 0;
+               
+                       FD_ZERO(&rfds);
+                       FD_SET(*fd, &rfds);
+                       if (select(*fd + 1, &rfds, NULL, NULL, &tv) == -1) {
                                *Error = strerror(errno);
-                                return -1;
-                        }
-                }
+                               close (*fd);
+                               *fd = -1;
+                               if (*Error == NULL)
+                                       *Error = ErrRBLF_SelectFailed;
+                               return -1;
+                       }
+                       if (! FD_ISSET(*fd, &rfds) != 0) {
+                               nSuccessLess ++;
+                               continue;
+                       }
+               }
 
                 if ((rlen = read(*fd, 
                                 ptr,
@@ -1985,14 +2005,17 @@ int StrBufReadBLOBBuffered(StrBuf *Blob,
        const char *pos;
        int nSelects = 0;
        int SelRes;
-        fd_set wset;
-        int fdflags;
+       int fdflags;
        int len = 0;
        int rlen, slen;
        int nRead = 0;
        int nAlreadyRead = 0;
+       int IsNonBlock;
        char *ptr;
+       fd_set rfds;
        const char *pch;
+       struct timeval tv;
+       int nSuccessLess;
 
        if ((Blob == NULL) || (*fd == -1) || (IOBuf == NULL) || (Pos == NULL))
                return -1;
@@ -2044,34 +2067,44 @@ int StrBufReadBLOBBuffered(StrBuf *Blob,
        slen = len = Blob->BufUsed;
 
        fdflags = fcntl(*fd, F_GETFL);
+       IsNonBlock = (fdflags & O_NONBLOCK) == O_NONBLOCK;
 
        SelRes = 1;
        nBytes -= nRead;
        nRead = 0;
        while (nRead < nBytes) {
-               if ((fdflags & O_NONBLOCK) == O_NONBLOCK) {
-                        FD_ZERO(&wset);
-                        FD_SET(*fd, &wset);
-                       SelRes = select(*fd + 1, NULL, &wset, NULL, NULL);
-               }
-               if (SelRes == -1) {
-                       *Error = strerror(errno);
-                       return -1;
-               }
-               else if (SelRes) {
-                       nSelects = 0;
-                       rlen = read(*fd, 
-                                   ptr,
-                                   nBytes - nRead);
-                       if (rlen == -1) {
-                               close(*fd);
-                               *fd = -1;
+               if (IsNonBlock)
+               {
+                       tv.tv_sec = 1;
+                       tv.tv_usec = 0;
+               
+                       FD_ZERO(&rfds);
+                       FD_SET(*fd, &rfds);
+                       if (select(*fd + 1, &rfds, NULL, NULL, &tv) == -1) {
                                *Error = strerror(errno);
-                               return rlen;
+                               close (*fd);
+                               *fd = -1;
+                               if (*Error == NULL)
+                                       *Error = ErrRBLF_SelectFailed;
+                               return -1;
+                       }
+                       if (! FD_ISSET(*fd, &rfds) != 0) {
+                               nSuccessLess ++;
+                               continue;
                        }
                }
-               else {
-                       nSelects ++;
+               nSuccessLess = 0;
+               rlen = read(*fd, 
+                           ptr,
+                           nBytes - nRead);
+               if (rlen == -1) {
+                       close(*fd);
+                       *fd = -1;
+                       *Error = strerror(errno);
+                       return rlen;
+               }
+               else if (rlen == 0){
+                       nSuccessLess ++;
                        if ((check == NNN_TERM) && 
                            (nRead > 5) &&
                            (strncmp(IOBuf->buf + IOBuf->BufUsed - 5, "\n000\n", 5) == 0)) 
@@ -2086,7 +2119,7 @@ int StrBufReadBLOBBuffered(StrBuf *Blob,
                                return -1;
                        }
                }
-               if (rlen > 0) {
+               else if (rlen > 0) {
                        nRead += rlen;
                        ptr += rlen;
                        IOBuf->BufUsed += rlen;