diff options
Diffstat (limited to 'stream/stm_read.c')
| -rw-r--r-- | stream/stm_read.c | 262 |
1 files changed, 262 insertions, 0 deletions
diff --git a/stream/stm_read.c b/stream/stm_read.c new file mode 100644 index 00000000..cb7c5c02 --- /dev/null +++ b/stream/stm_read.c @@ -0,0 +1,262 @@ +/*
+ * Input streams.
+ */
+
+#include "fitz.h"
+
+int
+fz_makedata(fz_stream *stm)
+{
+ fz_buffer *buf = stm->buffer;
+ fz_error *error;
+ fz_error *reason;
+ int produced;
+ int n;
+
+ if (stm->dead)
+ return -1;
+
+ if (stm->mode != FZ_SREAD)
+ return -1;
+
+ if (buf->eof)
+ return 0;
+
+ error = fz_rewindbuffer(buf);
+ if (error)
+ goto cleanup;
+
+ if (buf->ep - buf->wp == 0)
+ {
+ error = fz_growbuffer(buf);
+ if (error)
+ goto cleanup;
+ }
+
+ switch (stm->kind)
+ {
+
+ case FZ_SFILE:
+ n = read(stm->file, buf->wp, buf->ep - buf->wp);
+ if (n == -1)
+ {
+ stm->error = fz_throw("ioerror: read: %s", strerror(errno));
+ stm->dead = 1;
+ return -1;
+ }
+ if (n == 0)
+ buf->eof = 1;
+ buf->wp += n;
+ return n;
+
+ case FZ_SFILTER:
+ produced = 0;
+
+ while (1)
+ {
+ reason = fz_process(stm->filter, stm->chain->buffer, buf);
+
+ if (stm->filter->produced)
+ produced = 1;
+
+ if (reason == fz_ioneedin)
+ {
+ if (fz_makedata(stm->chain) < 0)
+ {
+ stm->dead = 1;
+ return -1;
+ }
+ }
+
+ else if (reason == fz_ioneedout)
+ {
+ if (produced)
+ return 0;
+
+ if (buf->rp > buf->bp)
+ {
+ error = fz_rewindbuffer(buf);
+ if (error)
+ goto cleanup;
+ }
+ else
+ {
+ error = fz_growbuffer(buf);
+ if (error)
+ goto cleanup;
+ }
+ }
+
+ else if (reason == fz_iodone)
+ {
+ return 0;
+ }
+
+ else
+ {
+ error = reason;
+ goto cleanup;
+ }
+ }
+
+ case FZ_SBUFFER:
+ return 0;
+ }
+
+ return -1;
+
+cleanup:
+ stm->error = error;
+ stm->dead = 1;
+ return -1;
+}
+
+int fz_rtell(fz_stream *stm)
+{
+ fz_buffer *buf = stm->buffer;
+ int t;
+
+ if (stm->dead)
+ return -1;
+
+ if (stm->mode != FZ_SREAD)
+ return -1;
+
+ switch (stm->kind)
+ {
+ case FZ_SFILE:
+ t = lseek(stm->file, 0, 1);
+ if (t < 0)
+ {
+ stm->dead = 1;
+ return -1;
+ }
+ return t - (buf->wp - buf->rp);
+
+ case FZ_SFILTER:
+ return stm->filter->count - (buf->wp - buf->rp);
+
+ case FZ_SBUFFER:
+ return buf->rp - buf->bp;
+ }
+
+ return -1;
+}
+
+int fz_rseek(fz_stream *stm, int offset, int whence)
+{
+ fz_buffer *buf = stm->buffer;
+ int t, c;
+
+ if (stm->dead)
+ return -1;
+
+ if (stm->mode != FZ_SREAD)
+ return -1;
+
+ if (whence == 1)
+ {
+ int cur = fz_rtell(stm);
+ if (cur < 0)
+ return -1;
+ offset = cur + offset;
+ whence = 0;
+ }
+
+ buf->eof = 0;
+
+ switch (stm->kind)
+ {
+ case FZ_SFILE:
+ t = lseek(stm->file, offset, whence);
+ if (t < 0)
+ {
+ stm->error = fz_throw("ioerror: lseek: %s", strerror(errno));
+ stm->dead = 1;
+ return -1;
+ }
+
+ buf->rp = buf->bp;
+ buf->wp = buf->bp;
+
+ return t;
+
+ case FZ_SFILTER:
+ if (whence == 0)
+ {
+ if (offset < fz_tell(stm))
+ {
+ stm->error = fz_throw("ioerror: cannot seek back in filter");
+ stm->dead = 1;
+ return -1;
+ }
+ while (fz_tell(stm) < offset)
+ {
+ c = fz_readbyte(stm);
+ if (c == EOF)
+ break;
+ }
+ return fz_tell(stm);
+ }
+ else
+ {
+ stm->dead = 1;
+ return -1;
+ }
+
+ case FZ_SBUFFER:
+ if (whence == 0)
+ buf->rp = CLAMP(buf->bp + offset, buf->bp, buf->ep);
+ else
+ buf->rp = CLAMP(buf->ep + offset, buf->bp, buf->ep);
+ return buf->rp - buf->bp;
+ }
+
+ return -1;
+}
+
+int fz_readbytex(fz_stream *stm)
+{
+ fz_buffer *buf = stm->buffer;
+ if (buf->rp == buf->wp)
+ {
+ if (buf->eof) return EOF;
+ if (fz_makedata(stm) < 0) return EOF;
+ }
+ if (buf->rp < buf->wp)
+ return *buf->rp++;
+ return EOF;
+}
+
+int fz_peekbytex(fz_stream *stm)
+{
+ fz_buffer *buf = stm->buffer;
+ if (buf->rp == buf->wp)
+ {
+ if (buf->eof) return EOF;
+ if (fz_makedata(stm) < 0) return EOF;
+ }
+ if (buf->rp < buf->wp)
+ return *buf->rp;
+ return EOF;
+}
+
+int fz_read(fz_stream *stm, unsigned char *mem, int n)
+{
+ fz_buffer *buf = stm->buffer;
+ int i = 0;
+
+ while (i < n)
+ {
+ while (buf->rp < buf->wp && i < n)
+ mem[i++] = *buf->rp++;
+ if (buf->rp == buf->wp)
+ {
+ if (buf->eof) return i;
+ if (fz_makedata(stm) < 0) return -1;
+ }
+ }
+
+ return i;
+}
+
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