diff options
Diffstat (limited to 'backend/epsonds-net.c')
| -rw-r--r-- | backend/epsonds-net.c | 158 |
1 files changed, 83 insertions, 75 deletions
diff --git a/backend/epsonds-net.c b/backend/epsonds-net.c index 8ea236b..3c8be29 100644 --- a/backend/epsonds-net.c +++ b/backend/epsonds-net.c @@ -32,11 +32,12 @@ #include "sane/sanei_debug.h" -static int +static ssize_t epsonds_net_read_raw(epsonds_scanner *s, unsigned char *buf, ssize_t wanted, SANE_Status *status) { - int ready, read = -1; + int ready; + ssize_t read = -1; fd_set readable; struct timeval tv; @@ -62,106 +63,98 @@ epsonds_net_read_raw(epsonds_scanner *s, unsigned char *buf, ssize_t wanted, return read; } -int -epsonds_net_read(epsonds_scanner *s, unsigned char *buf, ssize_t wanted, +static ssize_t +epsonds_net_read_buf(epsonds_scanner *s, unsigned char *buf, ssize_t wanted, SANE_Status * status) { - ssize_t size; ssize_t read = 0; - unsigned char header[12]; - /* read from buffer, if available */ - if (wanted && s->netptr != s->netbuf) { - DBG(23, "reading %lu from buffer at %p, %lu available\n", - (u_long) wanted, s->netptr, (u_long) s->netlen); + DBG(23, "%s: reading up to %lu from buffer at %p, %lu available\n", + __func__, (u_long) wanted, s->netptr, (u_long) s->netlen); - memcpy(buf, s->netptr, wanted); - read = wanted; + if ((size_t) wanted > s->netlen) { + *status = SANE_STATUS_IO_ERROR; + wanted = s->netlen; + } - s->netlen -= wanted; + memcpy(buf, s->netptr, wanted); + read = wanted; - if (s->netlen == 0) { - DBG(23, "%s: freeing %p\n", __func__, s->netbuf); - free(s->netbuf); - s->netbuf = s->netptr = NULL; - s->netlen = 0; - } + s->netptr += read; + s->netlen -= read; + + if (s->netlen == 0) { + DBG(23, "%s: freeing %p\n", __func__, s->netbuf); + free(s->netbuf); + s->netbuf = s->netptr = NULL; + s->netlen = 0; + } + + return read; +} + +ssize_t +epsonds_net_read(epsonds_scanner *s, unsigned char *buf, ssize_t wanted, + SANE_Status * status) +{ + if (wanted < 0) { + *status = SANE_STATUS_INVAL; + return 0; + } - return read; + size_t size; + ssize_t read = 0; + unsigned char header[12]; + + /* read from remainder of buffer */ + if (s->netptr) { + return epsonds_net_read_buf(s, buf, wanted, status); } /* receive net header */ - size = epsonds_net_read_raw(s, header, 12, status); - if (size != 12) { + read = epsonds_net_read_raw(s, header, 12, status); + if (read != 12) { return 0; } + /* validate header */ if (header[0] != 'I' || header[1] != 'S') { DBG(1, "header mismatch: %02X %02x\n", header[0], header[1]); *status = SANE_STATUS_IO_ERROR; return 0; } - // incoming payload size + /* parse payload size */ size = be32atoh(&header[6]); - DBG(23, "%s: wanted = %lu, available = %lu\n", __func__, - (u_long) wanted, (u_long) size); - *status = SANE_STATUS_GOOD; - if (size == wanted) { + if (!s->netbuf) { + DBG(15, "%s: direct read\n", __func__); + DBG(23, "%s: wanted = %lu, available = %lu\n", __func__, + (u_long) wanted, (u_long) size); - DBG(15, "%s: full read\n", __func__); - - if (size) { - read = epsonds_net_read_raw(s, buf, size, status); + if ((size_t) wanted > size) { + wanted = size; } - if (s->netbuf) { - free(s->netbuf); - s->netbuf = NULL; - s->netlen = 0; - } - - if (read < 0) { - return 0; - } - - } else if (wanted < size) { - - DBG(23, "%s: long tail\n", __func__); - - read = epsonds_net_read_raw(s, s->netbuf, size, status); - if (read != size) { - return 0; - } - - memcpy(buf, s->netbuf, wanted); - read = wanted; - - free(s->netbuf); - s->netbuf = NULL; - s->netlen = 0; - + read = epsonds_net_read_raw(s, buf, wanted, status); } else { + DBG(15, "%s: buffered read\n", __func__); + DBG(23, "%s: bufferable = %lu, available = %lu\n", __func__, + (u_long) s->netlen, (u_long) size); - DBG(23, "%s: partial read\n", __func__); - - read = epsonds_net_read_raw(s, s->netbuf, size, status); - if (read != size) { - return 0; + if (s->netlen > size) { + s->netlen = size; } - s->netlen = size - wanted; - s->netptr += wanted; - read = wanted; - - DBG(23, "0,4 %02x %02x\n", s->netbuf[0], s->netbuf[4]); - DBG(23, "storing %lu to buffer at %p, next read at %p, %lu bytes left\n", - (u_long) size, s->netbuf, s->netptr, (u_long) s->netlen); + /* fill buffer */ + read = epsonds_net_read_raw(s, s->netbuf, s->netlen, status); + s->netptr = s->netbuf; + s->netlen = (read > 0 ? read : 0); - memcpy(buf, s->netbuf, wanted); + /* copy wanted part */ + read = epsonds_net_read_buf(s, buf, wanted, status); } return read; @@ -175,23 +168,38 @@ epsonds_net_request_read(epsonds_scanner *s, size_t len) return status; } -int +size_t epsonds_net_write(epsonds_scanner *s, unsigned int cmd, const unsigned char *buf, size_t buf_size, size_t reply_len, SANE_Status *status) { unsigned char *h1, *h2; unsigned char *packet = malloc(12 + 8); - /* XXX check allocation failure */ + if (!packet) { + *status = SANE_STATUS_NO_MEM; + return 0; + } h1 = packet; // packet header h2 = packet + 12; // data header if (reply_len) { - s->netbuf = s->netptr = malloc(reply_len); + if (s->netbuf) { + DBG(23, "%s, freeing %p, %ld bytes unprocessed\n", + __func__, s->netbuf, (u_long) s->netlen); + free(s->netbuf); + s->netbuf = s->netptr = NULL; + s->netlen = 0; + } + s->netbuf = malloc(reply_len); + if (!s->netbuf) { + free(packet); + *status = SANE_STATUS_NO_MEM; + return 0; + } s->netlen = reply_len; - DBG(24, "allocated %lu bytes at %p\n", - (u_long) reply_len, s->netbuf); + DBG(24, "%s: allocated %lu bytes at %p\n", __func__, + (u_long) s->netlen, s->netbuf); } DBG(24, "%s: cmd = %04x, buf = %p, buf_size = %lu, reply_len = %lu\n", |