code.delx.au - pulseaudio/blob - src/iochannel.c

   1 #include <assert.h>
   2 #include <fcntl.h>
   3 #include <stdlib.h>
   4 #include <unistd.h>
   5
   6 #include "iochannel.h"
   7
   8 struct iochannel {
   9     int ifd, ofd;
  10     struct mainloop* mainloop;
  11
  12     void (*callback)(struct iochannel*io, void *userdata);
  13     void*userdata;
  14
  15     int readable;
  16     int writable;
  17
  18     int no_close;
  19
  20     struct mainloop_source* input_source, *output_source;
  21 };
  22
  23 static void enable_mainloop_sources(struct iochannel *io) {
  24     assert(io);
  25
  26     if (io->input_source == io->output_source) {
  27         enum mainloop_io_event e = MAINLOOP_IO_EVENT_NULL;
  28         assert(io->input_source);
  29
  30         if (!io->readable)
  31             e |= MAINLOOP_IO_EVENT_IN;
  32         if (!io->writable)
  33             e |= MAINLOOP_IO_EVENT_OUT;
  34
  35         mainloop_source_io_set_events(io->input_source, e);
  36     } else {
  37         if (io->input_source)
  38             mainloop_source_io_set_events(io->input_source, io->readable ? MAINLOOP_IO_EVENT_NULL : MAINLOOP_IO_EVENT_IN);
  39         if (io->output_source)
  40             mainloop_source_io_set_events(io->output_source, io->writable ? MAINLOOP_IO_EVENT_NULL : MAINLOOP_IO_EVENT_OUT);
  41     }
  42 }
  43
  44 static void callback(struct mainloop_source*s, int fd, enum mainloop_io_event events, void *userdata) {
  45     struct iochannel *io = userdata;
  46     int changed = 0;
  47     assert(s && fd >= 0 && userdata);
  48
  49     if ((events & MAINLOOP_IO_EVENT_IN) && !io->readable) {
  50         io->readable = 1;
  51         changed = 1;
  52     }
  53
  54     if ((events & MAINLOOP_IO_EVENT_OUT) && !io->writable) {
  55         io->writable = 1;
  56         changed = 1;
  57     }
  58
  59     if (changed) {
  60         enable_mainloop_sources(io);
  61
  62         if (io->callback)
  63             io->callback(io, io->userdata);
  64     }
  65 }
  66
  67 static void make_nonblock_fd(int fd) {
  68     int v;
  69
  70     if ((v = fcntl(fd, F_GETFL)) >= 0)
  71         if (!(v & O_NONBLOCK))
  72             fcntl(fd, F_SETFL, v|O_NONBLOCK);
  73 }
  74
  75 struct iochannel* iochannel_new(struct mainloop*m, int ifd, int ofd) {
  76     struct iochannel *io;
  77     assert(m && (ifd >= 0 || ofd >= 0));
  78
  79     io = malloc(sizeof(struct iochannel));
  80     io->ifd = ifd;
  81     io->ofd = ofd;
  82     io->mainloop = m;
  83
  84     io->userdata = NULL;
  85     io->callback = NULL;
  86     io->readable = 0;
  87     io->writable = 0;
  88     io->no_close = 0;
  89
  90     if (ifd == ofd) {
  91         assert(ifd >= 0);
  92         make_nonblock_fd(io->ifd);
  93         io->input_source = io->output_source = mainloop_source_new_io(m, ifd, MAINLOOP_IO_EVENT_IN|MAINLOOP_IO_EVENT_OUT, callback, io);
  94     } else {
  95
  96         if (ifd >= 0) {
  97             make_nonblock_fd(io->ifd);
  98             io->input_source = mainloop_source_new_io(m, ifd, MAINLOOP_IO_EVENT_IN, callback, io);
  99         } else
 100             io->input_source = NULL;
 101
 102         if (ofd >= 0) {
 103             make_nonblock_fd(io->ofd);
 104             io->output_source = mainloop_source_new_io(m, ofd, MAINLOOP_IO_EVENT_OUT, callback, io);
 105         } else
 106             io->output_source = NULL;
 107     }
 108
 109     return io;
 110 }
 111
 112 void iochannel_free(struct iochannel*io) {
 113     assert(io);
 114
 115     if (!io->no_close) {
 116         if (io->ifd >= 0)
 117             close(io->ifd);
 118         if (io->ofd >= 0 && io->ofd != io->ifd)
 119             close(io->ofd);
 120     }
 121
 122     if (io->input_source)
 123         mainloop_source_free(io->input_source);
 124     if (io->output_source && io->output_source != io->input_source)
 125         mainloop_source_free(io->output_source);
 126
 127     free(io);
 128 }
 129
 130 int iochannel_is_readable(struct iochannel*io) {
 131     assert(io);
 132     return io->readable;
 133 }
 134
 135 int iochannel_is_writable(struct iochannel*io) {
 136     assert(io);
 137     return io->writable;
 138 }
 139
 140 ssize_t iochannel_write(struct iochannel*io, const void*data, size_t l) {
 141     ssize_t r;
 142     assert(io && data && l && io->ofd >= 0);
 143
 144     if ((r = write(io->ofd, data, l)) >= 0) {
 145         io->writable = 0;
 146         enable_mainloop_sources(io);
 147     }
 148
 149     return r;
 150 }
 151
 152 ssize_t iochannel_read(struct iochannel*io, void*data, size_t l) {
 153     ssize_t r;
 154
 155     assert(io && data && l && io->ifd >= 0);
 156
 157     if ((r = read(io->ifd, data, l)) >= 0) {
 158         io->readable = 0;
 159         enable_mainloop_sources(io);
 160     }
 161
 162     return r;
 163 }
 164
 165 void iochannel_set_callback(struct iochannel*io, void (*callback)(struct iochannel*io, void *userdata), void *userdata) {
 166     assert(io);
 167     io->callback = callback;
 168     io->userdata = userdata;
 169 }
 170
 171 void iochannel_set_noclose(struct iochannel*io, int b) {
 172     assert(io);
 173     io->no_close = b;
 174 }