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

   1 #ifdef HAVE_CONFIG_H
   2 #include <config.h>
   3 #endif
   4
   5 #include <errno.h>
   6 #include <stdio.h>
   7 #include <assert.h>
   8 #include <stdlib.h>
   9 #include <string.h>
  10
  11 #include "ioline.h"
  12
  13 #define BUFFER_LIMIT (64*1024)
  14 #define READ_SIZE (1024)
  15
  16 struct pa_ioline {
  17     struct pa_iochannel *io;
  18     int dead;
  19
  20     char *wbuf;
  21     size_t wbuf_length, wbuf_index, wbuf_valid_length;
  22
  23     char *rbuf;
  24     size_t rbuf_length, rbuf_index, rbuf_valid_length;
  25
  26     void (*callback)(struct pa_ioline*io, const char *s, void *userdata);
  27     void *userdata;
  28 };
  29
  30 static void io_callback(struct pa_iochannel*io, void *userdata);
  31 static int do_write(struct pa_ioline *l);
  32
  33 struct pa_ioline* pa_ioline_new(struct pa_iochannel *io) {
  34     struct pa_ioline *l;
  35     assert(io);
  36
  37     l = malloc(sizeof(struct pa_ioline));
  38     assert(l);
  39     l->io = io;
  40     l->dead = 0;
  41
  42     l->wbuf = NULL;
  43     l->wbuf_length = l->wbuf_index = l->wbuf_valid_length = 0;
  44
  45     l->rbuf = NULL;
  46     l->rbuf_length = l->rbuf_index = l->rbuf_valid_length = 0;
  47
  48     l->callback = NULL;
  49     l->userdata = NULL;
  50
  51     pa_iochannel_set_callback(io, io_callback, l);
  52
  53     return l;
  54 }
  55
  56 void pa_ioline_free(struct pa_ioline *l) {
  57     assert(l);
  58     pa_iochannel_free(l->io);
  59     free(l->wbuf);
  60     free(l->rbuf);
  61     free(l);
  62 }
  63
  64 void pa_ioline_puts(struct pa_ioline *l, const char *c) {
  65     size_t len;
  66     assert(l && c);
  67
  68     len = strlen(c);
  69     if (len > BUFFER_LIMIT - l->wbuf_valid_length)
  70         len = BUFFER_LIMIT - l->wbuf_valid_length;
  71
  72     if (!len)
  73         return;
  74
  75     if (len > l->wbuf_length - l->wbuf_valid_length) {
  76         size_t n = l->wbuf_valid_length+len;
  77         char *new = malloc(n);
  78         if (l->wbuf) {
  79             memcpy(new, l->wbuf+l->wbuf_index, l->wbuf_valid_length);
  80             free(l->wbuf);
  81         }
  82         l->wbuf = new;
  83         l->wbuf_length = n;
  84         l->wbuf_index = 0;
  85     } else if (len > l->wbuf_length - l->wbuf_valid_length - l->wbuf_index) {
  86         memmove(l->wbuf, l->wbuf+l->wbuf_index, l->wbuf_valid_length);
  87         l->wbuf_index = 0;
  88     }
  89
  90     memcpy(l->wbuf+l->wbuf_index+l->wbuf_valid_length, c, len);
  91     l->wbuf_valid_length += len;
  92
  93     do_write(l);
  94 }
  95
  96 void pa_ioline_set_callback(struct pa_ioline*l, void (*callback)(struct pa_ioline*io, const char *s, void *userdata), void *userdata) {
  97     assert(l && callback);
  98     l->callback = callback;
  99     l->userdata = userdata;
 100 }
 101
 102 static int do_read(struct pa_ioline *l) {
 103     ssize_t r;
 104     size_t m, len;
 105     char *e;
 106     assert(l);
 107
 108     if (!pa_iochannel_is_readable(l->io))
 109         return 0;
 110
 111     len = l->rbuf_length - l->rbuf_index - l->rbuf_valid_length;
 112
 113     if (len < READ_SIZE) {
 114         size_t n = l->rbuf_valid_length+READ_SIZE;
 115
 116         if (n >= BUFFER_LIMIT)
 117             n = BUFFER_LIMIT;
 118
 119         if (l->rbuf_length >= n) {
 120             if (l->rbuf_valid_length)
 121                 memmove(l->rbuf, l->rbuf+l->rbuf_index, l->rbuf_valid_length);
 122         } else {
 123             char *new = malloc(n);
 124             if (l->rbuf_valid_length)
 125                 memcpy(new, l->rbuf+l->rbuf_index, l->rbuf_valid_length);
 126             free(l->rbuf);
 127             l->rbuf = new;
 128             l->rbuf_length = n;
 129         }
 130
 131         l->rbuf_index = 0;
 132     }
 133
 134     len = l->rbuf_length - l->rbuf_index - l->rbuf_valid_length;
 135
 136     if ((r = pa_iochannel_read(l->io, l->rbuf+l->rbuf_index+l->rbuf_valid_length, len)) <= 0)
 137         return -1;
 138
 139     e = memchr(l->rbuf+l->rbuf_index+l->rbuf_valid_length, '\n', r);
 140     l->rbuf_valid_length += r;
 141
 142     if (!e &&l->rbuf_valid_length >= BUFFER_LIMIT)
 143         e = l->rbuf+BUFFER_LIMIT-1;
 144
 145     if (e) {
 146         char *p;
 147
 148         *e = 0;
 149
 150         p = l->rbuf+l->rbuf_index;
 151         m = strlen(p);
 152
 153         l->rbuf_index += m+1;
 154         l->rbuf_valid_length -= m+1;
 155
 156         if (l->rbuf_valid_length == 0)
 157             l->rbuf_index = 0;
 158
 159         if (l->callback)
 160             l->callback(l, p, l->userdata);
 161     }
 162
 163     return 0;
 164 }
 165
 166 static int do_write(struct pa_ioline *l) {
 167     ssize_t r;
 168     assert(l);
 169
 170     if (!l->wbuf_valid_length || !pa_iochannel_is_writable(l->io))
 171         return 0;
 172
 173     if ((r = pa_iochannel_write(l->io, l->wbuf+l->wbuf_index, l->wbuf_valid_length)) < 0)
 174         return -1;
 175
 176     l->wbuf_valid_length -= r;
 177     if (l->wbuf_valid_length == 0)
 178         l->wbuf_index = 0;
 179
 180     return 0;
 181 }
 182
 183 static void io_callback(struct pa_iochannel*io, void *userdata) {
 184     struct pa_ioline *l = userdata;
 185     assert(io && l);
 186
 187     if (!l->dead && do_write(l) < 0)
 188         goto fail;
 189
 190     if (!l->dead && do_read(l) < 0)
 191         goto fail;
 192
 193     return;
 194
 195 fail:
 196     l->dead = 1;
 197     if (l->callback)
 198         l->callback(l, NULL, l->userdata);
 199 }