diff --git a/jcat.c b/jcat.c index 92c4f53..c299c31 100644 --- a/jcat.c +++ b/jcat.c @@ -14,6 +14,7 @@ #include #include #include +#include #include "libj1939.h" #define J1939_MAX_ETP_PACKET_SIZE (7 * 0x00ffffff) @@ -34,7 +35,7 @@ struct jcat_priv { int sock; int infile; int outfile; - unsigned int todo_send; + size_t max_transfer; int todo_prio; bool valid_peername; @@ -42,6 +43,8 @@ struct jcat_priv { bool todo_filesize; bool todo_connect; + unsigned long polltimeout; + struct sockaddr_can sockname; struct sockaddr_can peername; }; @@ -52,8 +55,10 @@ static const char help_msg[] = " FROM / TO - or [IFACE][:[SA][,[PGN][,NAME]]]\n" "Options:\n" " -i (default stdin)\n" - " -s[=LEN] Initial send of LEN bytes dummy data\n" + " -s Set maximal transfer size. Default: 117440505 byte\n" " -r Receive data\n" + " -P poll timeout in milliseconds before sending data.\n" + " With this option send() will be used with MSG_DONTWAIT flag.\n" "\n" "Example:\n" "jcat -i some_file_to_send can0:0x80 :0x90,0x12300\n" @@ -61,7 +66,7 @@ static const char help_msg[] = "\n" ; -static const char optstring[] = "?i:vs::rp:cnw::"; +static const char optstring[] = "?i:vs:rp:P:cnw::"; static void jcat_init_sockaddr_can(struct sockaddr_can *sac) @@ -72,16 +77,108 @@ static void jcat_init_sockaddr_can(struct sockaddr_can *sac) sac->can_addr.j1939.pgn = J1939_NO_PGN; } +static ssize_t jcat_send_one(struct jcat_priv *priv, int out_fd, + const void *buf, size_t buf_size) +{ + ssize_t num_sent; + int flags = 0; + + if (priv->polltimeout) + flags |= MSG_DONTWAIT; + + if (priv->valid_peername && !priv->todo_connect) + num_sent = sendto(out_fd, buf, buf_size, flags, + (struct sockaddr *)&priv->peername, + sizeof(priv->peername)); + else + num_sent = send(out_fd, buf, buf_size, flags); + + if (num_sent == -1) { + warn("%s: transfer error: %i", __func__, -errno); + return -errno; + } + + if (num_sent == 0) /* Should never happen */ { + warn("%s: transferred 0 bytes", __func__); + return -EINVAL; + } + + if (num_sent > buf_size) /* Should never happen */ { + warn("%s: send more then read", __func__); + return -EINVAL; + } + + return num_sent; +} + +static int jcat_poll(struct jcat_priv *priv) +{ + struct pollfd fds = { + .fd = priv->sock, + .events = POLLOUT, + }; + int ret; + + if (!priv->polltimeout) + return 0; + + ret = poll(&fds, 1, priv->polltimeout); + if (ret < 0) + return -errno; + else if (!ret) { + warn("%s: timeout", __func__); + return -ETIME; + } + + if (!(fds.revents & POLLOUT)) { + warn("%s: something else is wrong", __func__); + return -EIO; + } + + return 0; +} + +static int jcat_send_loop(struct jcat_priv *priv, int out_fd, char *buf, + size_t buf_size) +{ + ssize_t count, num_sent; + char *tmp_buf = buf; + int ret; + + count = buf_size; + + while (count) { + ret = jcat_poll(priv); + if (ret) { + if (ret == -EINTR) + continue; + else + return ret; + } + num_sent = jcat_send_one(priv, out_fd, tmp_buf, count); + if (num_sent < 0) + return num_sent; + + count -= num_sent; + tmp_buf += num_sent; + if (buf + buf_size < tmp_buf + count) { + warn("%s: send buffer is bigger than the read buffer", + __func__); + return -EINVAL; + } + } + return 0; +} + static int jcat_sendfile(struct jcat_priv *priv, int out_fd, int in_fd, off_t *offset, size_t count) { int ret = EXIT_SUCCESS; off_t orig = 0; char *buf; - size_t to_read, num_read, num_sent, tot_sent, buf_size; - int round = 0; + size_t to_read, num_read, buf_size; - buf_size = min((size_t)J1939_MAX_ETP_PACKET_SIZE, count); + buf_size = min(priv->max_transfer, count); buf = malloc(buf_size); if (!buf) { warn("can't allocate buf"); @@ -104,8 +201,6 @@ static int jcat_sendfile(struct jcat_priv *priv, int out_fd, int in_fd, } } - tot_sent = 0; - while (count > 0) { to_read = min(buf_size, count); @@ -117,35 +212,11 @@ static int jcat_sendfile(struct jcat_priv *priv, int out_fd, int in_fd, if (num_read == 0) break; /* EOF */ - if (priv->valid_peername && !priv->todo_connect) - num_sent = sendto(out_fd, buf, num_read, 0, - (void *)&priv->peername, - sizeof(priv->peername)); - else - num_sent = send(out_fd, buf, num_read, 0); - - if (num_sent == -1) { - warn("sendfile: write() transferr error"); - ret = EXIT_FAILURE; + ret = jcat_send_loop(priv, out_fd, buf, num_read); + if (ret) goto do_free; - } - if (num_sent == 0) /* Should never happen */ { - warn("sendfile: write() transferred 0 bytes"); - ret = EXIT_FAILURE; - goto do_free; - } - - if (num_sent != num_read) { - warn("sendfile: write() not full transfer: %zi %zi", - num_sent, num_read); - ret = EXIT_FAILURE; - goto do_free; - } - - round++; - count -= num_sent; - tot_sent += num_sent; + count -= num_read; } if (offset) { @@ -186,15 +257,16 @@ static size_t jcat_get_file_size(int fd) static int jcat_send(struct jcat_priv *priv) { + unsigned int size = 0; if (priv->todo_filesize) - priv->todo_send = jcat_get_file_size(priv->infile); + size = jcat_get_file_size(priv->infile); - if (!priv->todo_send) + if (!size) return EXIT_FAILURE; return jcat_sendfile(priv, priv->sock, priv->infile, NULL, - priv->todo_send); + size); } static int jcat_recv_one(struct jcat_priv *priv, uint8_t *buf, size_t buf_size) @@ -222,7 +294,7 @@ static int jcat_recv(struct jcat_priv *priv) size_t buf_size; uint8_t *buf; - buf_size = J1939_MAX_ETP_PACKET_SIZE; + buf_size = priv->max_transfer; buf = malloc(buf_size); if (!buf) { warn("can't allocate rx buf"); @@ -296,7 +368,10 @@ static int jcat_parse_args(struct jcat_priv *priv, int argc, char *argv[]) priv->todo_filesize = 1; break; case 's': - priv->todo_send = strtoul(optarg ?: "8", NULL, 0); + priv->max_transfer = strtoul(optarg, NULL, 0); + if (priv->max_transfer > J1939_MAX_ETP_PACKET_SIZE) + err(EXIT_FAILURE, "used value (%zu) is bigger then allowed maximal size: %u.\n", + priv->max_transfer, J1939_MAX_ETP_PACKET_SIZE); break; case 'r': priv->todo_recv = 1; @@ -304,6 +379,9 @@ static int jcat_parse_args(struct jcat_priv *priv, int argc, char *argv[]) case 'p': priv->todo_prio = strtoul(optarg, NULL, 0); break; + case 'P': + priv->polltimeout = strtoul(optarg, NULL, 0); + break; case 'c': priv->todo_connect = 1; break; @@ -343,6 +421,7 @@ int main(int argc, char *argv[]) priv->todo_prio = -1; priv->infile = STDIN_FILENO; priv->outfile = STDOUT_FILENO; + priv->max_transfer = J1939_MAX_ETP_PACKET_SIZE; jcat_init_sockaddr_can(&priv->sockname); jcat_init_sockaddr_can(&priv->peername);