Annotation of libwww/Library/src/HTChannl.c, revision 2.11

2.1       frystyk     1: /*                                                                  HTChannl.c
                      2: **     CONTAINS STREAMS FOR READING AND WRITING TO AND FROM A TRANSPORT
                      3: **
                      4: **     (c) COPYRIGHT MIT 1995.
                      5: **     Please first read the full copyright statement in the file COPYRIGH.
2.11    ! frystyk     6: **     @(#) $Id: HTChannl.c,v 2.10 1996/08/19 18:30:18 frystyk Exp $
2.1       frystyk     7: **
                      8: **
                      9: ** HISTORY:
                     10: **     April 96  HFN   Written
                     11: */
                     12: 
                     13: /* Library Include files */
                     14: #include "sysdep.h"
                     15: #include "WWWUtil.h"
                     16: #include "HTAlert.h"
2.10      frystyk    17: #include "HTHost.h"
2.1       frystyk    18: #include "HTError.h"
                     19: #include "HTChannl.h"                                   /* Implemented here */
                     20: 
                     21: #define HASH_SIZE      67
                     22: #define HASH(s)                ((s) % HASH_SIZE)
                     23: 
                     24: struct _HTChannel {
                     25:     SOCKET             sockfd;                                    /* Socket */
                     26:     FILE *             fp;
                     27:     HTInputStream *    input;                               /* Input stream */
                     28:     HTOutputStream *   output;                             /* Output stream */
                     29:     BOOL               active;                 /* Active or passive channel */
                     30:     int                        semaphore;                         /* On channel use */
2.10      frystyk    31:     HTHost *           host;                          /* Zombie connections */
2.1       frystyk    32: };
                     33: 
                     34: struct _HTInputStream {
                     35:     const HTInputStreamClass * isa;    
                     36: };
                     37: 
                     38: struct _HTOutputStream {
                     39:     const HTOutputStreamClass *        isa;    
                     40: };
                     41: 
                     42: PRIVATE HTList ** channels = NULL;                      /* List of channels */
                     43: 
                     44: /* ------------------------------------------------------------------------- */
                     45: 
                     46: PRIVATE void free_channel (HTChannel * ch)
                     47: {
                     48:     if (ch) {
                     49: 
                     50:        /* Close the input and output stream */
2.11    ! frystyk    51:        if (ch->input) {
        !            52:            (*ch->input->isa->close)(ch->input);
        !            53:            ch->input = NULL;
        !            54:        }
        !            55:        if (ch->output) {
        !            56:            (*ch->output->isa->close)(ch->output);
        !            57:            ch->output = NULL;
        !            58:        }
2.1       frystyk    59: 
                     60:        /* Close the socket */
                     61:        if (ch->sockfd != INVSOC) {
                     62:            NETCLOSE(ch->sockfd);
2.3       eric       63:            HTEvent_unregister(ch->sockfd, (SockOps) FD_ALL);
2.10      frystyk    64:            HTNet_decreaseSocket();
2.1       frystyk    65:            if (PROT_TRACE)
                     66:                HTTrace("Channel..... Deleted %p, socket %d\n", ch,ch->sockfd);
                     67:        }
                     68: 
                     69:        /* Close the file */
                     70:        if (ch->fp) {
                     71:            fclose(ch->fp);
                     72:            if (PROT_TRACE)
                     73:                HTTrace("Channel..... Deleted %p, file %p\n", ch, ch->fp);
                     74:        }
                     75:        HT_FREE(ch);
                     76:     }
                     77: }
                     78: 
                     79: /*
                     80: **     A channel is uniquely identified by a socket.
                     81: **     Note that we don't create the input and output stream - they are 
2.10      frystyk    82: **     created later.
2.1       frystyk    83: **
                     84: **     We only keep a hash on sockfd's as we don't have to look for channels
                     85: **     for ANSI file descriptors.
                     86: */
                     87: PUBLIC HTChannel * HTChannel_new (HTNet * net, BOOL active)
                     88: {
                     89:     if (net) {
                     90:        HTList * list = NULL;
                     91:        HTChannel * ch = NULL;
2.5       frystyk    92:        SOCKET sockfd = HTNet_socket(net);
                     93:        int hash = sockfd < 0 ? 0 : HASH(sockfd);
2.1       frystyk    94:        if (PROT_TRACE) HTTrace("Channel..... Hash value is %d\n", hash);
                     95:        if (!channels) {
                     96:            if (!(channels = (HTList **) HT_CALLOC(HASH_SIZE,sizeof(HTList*))))
                     97:                HT_OUTOFMEM("HTChannel_new");
                     98:        }
                     99:        if (!channels[hash]) channels[hash] = HTList_new();
                    100:        list = channels[hash];
                    101:        if ((ch = (HTChannel *) HT_CALLOC(1, sizeof(HTChannel))) == NULL)
                    102:            HT_OUTOFMEM("HTChannel_new");           
2.5       frystyk   103:        ch->sockfd = sockfd;
2.1       frystyk   104:        ch->active = active;
                    105:        ch->semaphore = 1;
                    106:        HTList_addObject(list, (void *) ch);
                    107:        if (PROT_TRACE) HTTrace("Channel..... Added %p to list %p\n", ch,list);
                    108:        return ch;
                    109:     }
                    110:     return NULL;
                    111: }
                    112: 
                    113: /*
                    114: **     Look for a channel object if we for some reason should have lost it
                    115: **     Returns NULL if nothing found
                    116: */
                    117: PUBLIC HTChannel * HTChannel_find (SOCKET sockfd)
                    118: {
                    119:     if (channels && sockfd != INVSOC) {
                    120:        int hash = HASH(sockfd);
                    121:        HTList * list = channels[hash];
                    122:        if (list) {
                    123:            HTChannel * ch = NULL;
                    124:            while ((ch = (HTChannel *) HTList_nextObject(list)))
                    125:                if (ch->sockfd == sockfd) return ch;
                    126:        }
                    127:     }
                    128:     return NULL;
                    129: }
                    130: 
                    131: /*
                    132: **     When deleting a channel we first look at if there are no more requests
                    133: **     using the channel (the semaphore is <= 0). Then, if the socket supports
                    134: **     persistent connections then we register the channel in the Host cache
                    135: **     and wait until the other end closes it or we get a time out on our side
                    136: */
2.6       eric      137: PUBLIC BOOL HTChannel_delete (HTChannel * channel, int status)
2.1       frystyk   138: {
                    139:     if (channel) {
2.2       frystyk   140:        if (PROT_TRACE) HTTrace("Channel..... Delete %p with semaphore %d\n",
2.1       frystyk   141:                                channel, channel->semaphore);
                    142:        /*
                    143:        **  We call the free methods on both the input stream and the output
                    144:        **  stream so that we can free up the stream pipes. However, note that
                    145:        **  this doesn't mean that we close the input stream and output stream
                    146:        **  them selves - only the generic streams
                    147:        */
2.6       eric      148:        if (channel->input) 
                    149:            if (status == HT_INTERRUPTED)
                    150:                (*channel->input->isa->abort)(channel->input, NULL);
                    151:            else
                    152:                (*channel->input->isa->_free)(channel->input);
                    153:        if (channel->output)
                    154:            if (status == HT_INTERRUPTED)
                    155:                (*channel->output->isa->abort)(channel->output, NULL);
                    156:            else
                    157:                (*channel->output->isa->_free)(channel->output);
2.1       frystyk   158: 
                    159:        /*
                    160:        **  Check whether this channel is used by other objects or we can
                    161:        **  delete it and free memory.
                    162:        */
                    163:        if (channel->semaphore <= 0 && channels) {
                    164:            int hash = HASH(channel->sockfd);
                    165:            HTList * list = channels[hash];
                    166:            if (list) {
                    167:                HTList_removeObject(list, (void *) channel);
                    168:                free_channel(channel);
                    169:                return YES;
                    170:            }
2.8       frystyk   171:        } else
                    172:            HTChannel_downSemaphore(channel);
2.1       frystyk   173:     }
                    174:     return NO;
                    175: }
                    176: 
                    177: /*     HTChannel_deleteAll
                    178: **     -------------------
                    179: **     Destroys all channels. This is called by HTLibTerminate(0
                    180: */
2.9       frystyk   181: PUBLIC BOOL HTChannel_deleteAll (void)
2.1       frystyk   182: {
                    183:     if (channels) {
                    184:        HTList * cur;
                    185:        int cnt;
                    186:        for (cnt=0; cnt<HASH_SIZE; cnt++) {
                    187:            if ((cur = channels[cnt])) { 
                    188:                HTChannel * pres;
                    189:                while ((pres = (HTChannel *) HTList_nextObject(cur)) != NULL)
                    190:                    free_channel(pres);
                    191:            }
                    192:            HTList_delete(channels[cnt]);
                    193:        }
                    194:        HT_FREE(channels);
                    195:     }
                    196:     return YES;
                    197: }
                    198: 
                    199: /*
2.10      frystyk   200: **     Return the socket associated with this channel
2.1       frystyk   201: */
2.10      frystyk   202: PUBLIC SOCKET HTChannel_socket (HTChannel * channel)
2.1       frystyk   203: {
2.10      frystyk   204:     return channel ? channel->sockfd : INVSOC;
2.1       frystyk   205: }
                    206: 
2.10      frystyk   207: /*
                    208: **     Return the file descriptor associated with this channel
                    209: */
                    210: PUBLIC FILE * HTChannel_file (HTChannel * channel)
2.1       frystyk   211: {
2.10      frystyk   212:     return channel ? channel->fp : NULL;
2.1       frystyk   213: }
                    214: 
                    215: /*
2.10      frystyk   216: **     We keep the associated Host object in case we have a
                    217: **     sleeping connection. 
2.1       frystyk   218: */
2.10      frystyk   219: PUBLIC BOOL HTChannel_setHost (HTChannel * ch, HTHost * host)
2.1       frystyk   220: {
2.10      frystyk   221:     if (ch && host) {
                    222:        ch->host = host;
                    223:        return YES;
                    224:     }
                    225:     return NO;
2.4       frystyk   226: }
                    227: 
2.10      frystyk   228: PUBLIC HTHost * HTChannel_host (HTChannel * ch)
2.4       frystyk   229: {
2.10      frystyk   230:     return (ch ? ch->host : NULL);
2.1       frystyk   231: }
                    232: 
                    233: /*
                    234: **     Increase the semaphore for this channel
                    235: */
                    236: PUBLIC void HTChannel_upSemaphore (HTChannel * channel)
                    237: {
                    238:     if (channel) {
                    239:        channel->semaphore++;
                    240:        if (PROT_TRACE)
                    241:            HTTrace("Channel..... Semaphore increased to %d for channel %p\n",
                    242:                    channel->semaphore, channel);
                    243:     }
                    244: }
                    245: 
                    246: /*
                    247: **     Decrease the semaphore for this channel
                    248: */
                    249: PUBLIC void HTChannel_downSemaphore (HTChannel * channel)
                    250: {
                    251:     if (channel) {
                    252:        channel->semaphore--;
                    253:        if (channel->semaphore <= 0) channel->semaphore = 0;
                    254:        if (PROT_TRACE)
                    255:            HTTrace("Channel..... Semaphore decreased to %d for channel %p\n",
2.7       frystyk   256:                    channel->semaphore, channel);
                    257:     }
                    258: }
                    259: 
                    260: /*
                    261: **     Explicitly set the semaphore for this channel
                    262: */
                    263: PUBLIC void HTChannel_setSemaphore (HTChannel * channel, int semaphore)
                    264: {
                    265:     if (channel) {
                    266:        channel->semaphore = semaphore;
                    267:        if (channel->semaphore <= 0) channel->semaphore = 0;
                    268:        if (PROT_TRACE)
                    269:            HTTrace("Channel..... Semaphore set to %d for channel %p\n",
2.1       frystyk   270:                    channel->semaphore, channel);
                    271:     }
                    272: }
                    273: 
                    274: /*
                    275: **     Create the input stream and bind it to the channel
                    276: **     Please read the description in the HTIOStream module on the parameters
                    277: */
2.10      frystyk   278: PUBLIC BOOL HTChannel_setInput (HTChannel * ch, HTInputStream * input)
2.1       frystyk   279: {
                    280:     if (ch) {
                    281:        ch->input = input;
                    282:        return YES;
                    283:     }
                    284:     return NO;
                    285: }
                    286: 
                    287: PUBLIC HTInputStream * HTChannel_input (HTChannel * ch)
                    288: {
                    289:     return ch ? ch->input : NULL;
                    290: }
                    291: 
                    292: /*
                    293: **     Create the output stream and bind it to the channel
                    294: **     Please read the description in the HTIOStream module on the parameters
                    295: */
2.10      frystyk   296: PUBLIC BOOL HTChannel_setOutput (HTChannel * ch, HTOutputStream * output)
2.1       frystyk   297: {
                    298:     if (ch) {
                    299:        ch->output = output;
                    300:        return YES;
                    301:     }
                    302:     return NO;
                    303: }
                    304: 
                    305: PUBLIC HTOutputStream * HTChannel_output (HTChannel * ch)
                    306: {
                    307:     return ch ? ch->output : NULL;
                    308: }
                    309: 

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