From 4e05e2ffe67e922980dd9efda6790ccdfcda6ac4 Mon Sep 17 00:00:00 2001 From: Ludovic Pouzenc Date: Sun, 3 Jul 2016 10:46:30 +0200 Subject: Refactor, keep tracing on stderr, corrections for iovec size and dup dgram handling. --- mcastseed/src/dgrambuf.c | 169 +++++++++++++++++++++++++++-------------------- 1 file changed, 98 insertions(+), 71 deletions(-) (limited to 'mcastseed/src/dgrambuf.c') diff --git a/mcastseed/src/dgrambuf.c b/mcastseed/src/dgrambuf.c index b07ba1f..b19b698 100644 --- a/mcastseed/src/dgrambuf.c +++ b/mcastseed/src/dgrambuf.c @@ -12,6 +12,7 @@ #include /* perror() */ #include /* memset() */ #include /* writev() */ +#include /* MIN() */ struct uint_pair { unsigned int index; @@ -19,17 +20,19 @@ struct uint_pair { }; struct dgrambuf_t { - size_t dgram_count; + size_t dgram_slots; + size_t dgram_free_count; size_t dgram_max_size; size_t dgram_header_size; - struct iovec *recv_iovecs; - struct iovec *write_iovecs; + size_t iovec_slots; + struct iovec *iov_recv; + struct iovec *iov_write; struct mmsghdr *msgs; - unsigned int win_base; - unsigned int *dgram_seq_numbers; /* Stores the decoded datagram sequence number for each dgram slot of buf */ + unsigned int dgram_seq_base; unsigned int *dgram_len; + unsigned int *dgram_seq_numbers; /* Stores the decoded datagram sequence number for each dgram slot of buf */ struct uint_pair *dgram_ordered_seq_numbers; void *buf; @@ -44,33 +47,40 @@ void dgrambuf_set_validate_func(dgrambuf_t dbuf, unsigned int (*func)(unsigned i dbuf->validate_func = func; } +size_t dgrambuf_free_count(const dgrambuf_t dbuf) { + return dbuf->dgram_free_count; +} + int dgrambuf_recvmmsg(dgrambuf_t dbuf, int sockfd) { void *dgram_base; size_t vlen, i, dgram_index; int recv_msg_count, res; unsigned int seq, dgram_len; - if ( !dbuf->validate_func ) { + /* Buffer is full, can't receive */ + if ( dbuf->dgram_free_count == 0 ) { return -1; } + /* Validate function is mandatory */ + if ( !dbuf->validate_func ) { + return -2; + } + /* Initialize recvmmsg() syscall arguments */ - for (i=0, vlen=0; i < dbuf->dgram_count; i++) { + for (i=0, vlen=0; i < dbuf->dgram_slots; i++) { if ( dbuf->dgram_seq_numbers[i] == 0 ) { - dbuf->recv_iovecs[vlen].iov_base = dbuf->buf + i*dbuf->dgram_max_size; - dbuf->recv_iovecs[vlen].iov_len = dbuf->dgram_max_size; + dbuf->iov_recv[vlen].iov_base = dbuf->buf + i*dbuf->dgram_max_size; + dbuf->iov_recv[vlen].iov_len = dbuf->dgram_max_size; memset(dbuf->msgs + vlen, 0, sizeof(struct mmsghdr)); - dbuf->msgs[vlen].msg_hdr.msg_iov = dbuf->recv_iovecs + vlen; + dbuf->msgs[vlen].msg_hdr.msg_iov = dbuf->iov_recv + vlen; dbuf->msgs[vlen].msg_hdr.msg_iovlen = 1; vlen++; + if ( vlen == dbuf->iovec_slots ) + break; } } - /* Buffer is full, can't receive */ - if ( vlen==0 ) { - return -2; - } - /* Do the syscall */ recv_msg_count = recvmmsg(sockfd, dbuf->msgs, vlen, MSG_WAITFORONE, NULL); if (recv_msg_count < 0) { @@ -81,28 +91,29 @@ int dgrambuf_recvmmsg(dgrambuf_t dbuf, int sockfd) { /* Check all received messages */ res = 1; for (i=0; irecv_iovecs[i].iov_base; + dgram_base = dbuf->iov_recv[i].iov_base; dgram_index = (dgram_base - dbuf->buf) / dbuf->dgram_max_size; dgram_len = dbuf->msgs[i].msg_len; seq = dbuf->validate_func(dgram_len, dgram_base); // TODO better feedback if ( seq == 0 ) { - printf("#%zi invalid (%u)\n", i, seq); + fprintf(stderr, "dgrambuf_recvmmsg(): #%zi invalid (%u)\n", i, seq); dbuf->dgram_seq_numbers[dgram_index] = 0; } else if ( seq == -1 ) { - printf("#%zi end\n", i); + fprintf(stderr, "dgrambuf_recvmmsg(): #%zi end\n", i); dbuf->dgram_seq_numbers[dgram_index] = 0; res = 0; - } else if ( seq < dbuf->win_base ) { - printf("#%zi past (%u)\n", i, seq); + } else if ( seq < dbuf->dgram_seq_base ) { + fprintf(stderr, "dgrambuf_recvmmsg(): #%zi past (%u)\n", i, seq); dbuf->dgram_seq_numbers[dgram_index] = 0; - } else if ( seq >= dbuf->win_base + dbuf->dgram_count ) { - printf("#%zi future (%u)\n", i, seq); + } else if ( seq >= dbuf->dgram_seq_base + dbuf->dgram_slots ) { + fprintf(stderr, "dgrambuf_recvmmsg(): #%zi future (%u)\n", i, seq); dbuf->dgram_seq_numbers[dgram_index] = 0; } else { - printf("#%zi valid (%u)\n", i, seq); + //fprintf(stderr, "dgrambuf_recvmmsg(): #%zi valid (%u)\n", i, seq); dbuf->dgram_seq_numbers[dgram_index] = seq; dbuf->dgram_len[dgram_index] = dgram_len; + dbuf->dgram_free_count--; } } @@ -114,40 +125,52 @@ ssize_t dgrambuf_write(dgrambuf_t dbuf, int fd) { unsigned int curr_seq, prev_seq, dgram_len; ssize_t nwrite, total; + /* Buffer is empty, nothing to write */ + if ( dbuf->dgram_free_count == dbuf->dgram_slots ) { + return -1; + } + /* Initialize dgram_ordered_seq_numbers from dgram_seq_numbers */ - for (i=0; i < dbuf->dgram_count; i++) { + for (i=0; i < dbuf->dgram_slots; i++) { dbuf->dgram_ordered_seq_numbers[i].index = i; dbuf->dgram_ordered_seq_numbers[i].value = dbuf->dgram_seq_numbers[i]; } /* Inplace sorting of dgram_ordered_seq_numbers */ - qsort(dbuf->dgram_ordered_seq_numbers, dbuf->dgram_count, sizeof(struct uint_pair), _compare_uint_pair); + qsort(dbuf->dgram_ordered_seq_numbers, dbuf->dgram_slots, sizeof(struct uint_pair), _compare_uint_pair); /* Initialize iovecs for writev, take dgram payloads following the sequence numbers */ - for (prev_seq=0, vlen=0, total=0, i=0; i< dbuf->dgram_count; i++) { + prev_seq=0, vlen=0, total=0; + for (i=dbuf->dgram_free_count; i < dbuf->dgram_slots; i++) { curr_seq = dbuf->dgram_ordered_seq_numbers[i].value; /* Skip empty dgram slot */ - if ( curr_seq == 0 ) + if ( curr_seq == 0 ) { + fprintf(stderr, "Oops : found empty slot (i==%zi)\n", i); + continue; + } + + /* Skip if current dgram is a dup of the previous */ + if ( curr_seq == prev_seq ) { + dgram_index = dbuf->dgram_ordered_seq_numbers[i].index; + /* Mark slot as empty */ + dbuf->dgram_seq_numbers[dgram_index] = 0; + dbuf->dgram_free_count++; continue; + } /* Skip dgram comming from the past */ - if ( curr_seq < dbuf->win_base ) { + if ( curr_seq < dbuf->dgram_seq_base ) { fprintf(stderr, "Oops : found dgram from past in buffer (%u)\n", curr_seq); continue; } - /* Break if first dgram to write is not in buffer at all */ - if ( ( vlen==0 ) && (curr_seq != dbuf->win_base) ) { - fprintf(stderr, "Oops : nothing to write, missing %u seq\n", dbuf->win_base); + /* Stop if first dgram to write is not in buffer at all */ + if ( ( vlen==0 ) && (curr_seq != dbuf->dgram_seq_base) ) { + fprintf(stderr, "Oops : nothing to write, missing %u seq\n", dbuf->dgram_seq_base); break; } - /* Skip if next dgram is a dup */ - if ( ( vlen > 0 ) && (curr_seq == prev_seq) ) { - continue; - } - - /* Break if next seq dgram is missing */ + /* Stop if current seq dgram is missing */ if ( ( vlen > 0 ) && (curr_seq > prev_seq+1 ) ) { break; } @@ -156,87 +179,91 @@ ssize_t dgrambuf_write(dgrambuf_t dbuf, int fd) { dgram_index = dbuf->dgram_ordered_seq_numbers[i].index; dgram_len = dbuf->dgram_len[dgram_index] - dbuf->dgram_header_size; - dbuf->write_iovecs[vlen].iov_len = dgram_len; /* Setup iovecs */ - dbuf->write_iovecs[vlen].iov_base = dbuf->buf + dgram_index*dbuf->dgram_max_size + dbuf->dgram_header_size; - dbuf->dgram_seq_numbers[dgram_index] = 0; /* Mark dgram slots about to be written out as reusable */ + dbuf->iov_write[vlen].iov_len = dgram_len; /* Setup iovecs */ + dbuf->iov_write[vlen].iov_base = dbuf->buf + dgram_index*dbuf->dgram_max_size + dbuf->dgram_header_size; + dbuf->dgram_seq_numbers[dgram_index] = 0; /* Mark dgram slots about to be written out as empty for next read */ total += dgram_len; /* Update counters */ - vlen++; - dbuf->win_base = curr_seq; + dbuf->dgram_free_count++; + dbuf->dgram_seq_base = curr_seq + 1; prev_seq = curr_seq; + vlen++; + /* Don't plan to write more than iovec_slots slots */ + if ( vlen == dbuf->iovec_slots ) + break; } - /* If nothing valid to write out */ + /* Nothing valid to write out (but buffer not empty, missing the next dgram) */ if ( vlen == 0 ) { return -1; } - nwrite = writev(fd, dbuf->write_iovecs, vlen); + nwrite = writev(fd, dbuf->iov_write, vlen); if ( nwrite < 0 ) { perror("writev()"); - return nwrite; - } - - if ( nwrite != total ) { + } else if ( nwrite != total ) { + //FIXME : everything break if there because all non writed data will be overwritted at next read + // Make a loop here could make dgrambuf_writev() unbounded in run time fprintf(stderr, "writev() short\n"); - return nwrite; } return nwrite; } -dgrambuf_t dgrambuf_new(size_t dgram_count, size_t dgram_max_size, size_t dgram_header_size) { +dgrambuf_t dgrambuf_new(size_t dgram_slots, size_t dgram_max_size, size_t dgram_header_size, size_t iovec_slots) { dgrambuf_t dbuf = calloc(1, sizeof(struct dgrambuf_t)); if (!dbuf) goto fail0; - dbuf->dgram_count = dgram_count; + dbuf->dgram_slots = dgram_slots; + dbuf->dgram_free_count = dgram_slots; dbuf->dgram_max_size = dgram_max_size; dbuf->dgram_header_size = dgram_header_size; + dbuf->iovec_slots = MIN(iovec_slots,dgram_slots); - dbuf->recv_iovecs = calloc(dgram_count, sizeof(struct iovec)); - if (!dbuf->recv_iovecs) goto fail1; + dbuf->iov_recv = calloc(iovec_slots, sizeof(struct iovec)); + if (!dbuf->iov_recv) goto fail1; - dbuf->write_iovecs = calloc(dgram_count, sizeof(struct iovec)); - if (!dbuf->write_iovecs) goto fail2; + dbuf->iov_write = calloc(iovec_slots, sizeof(struct iovec)); + if (!dbuf->iov_write) goto fail2; - dbuf->msgs = calloc(dgram_count, sizeof(struct mmsghdr)); + dbuf->msgs = calloc(iovec_slots, sizeof(struct mmsghdr)); if (!dbuf->msgs) goto fail3; - dbuf->win_base = 1; - dbuf->dgram_seq_numbers = calloc(dgram_count, sizeof(unsigned int)); - if (!dbuf->dgram_seq_numbers) goto fail4; + dbuf->dgram_seq_base = 1; + dbuf->dgram_len = calloc(dgram_slots, sizeof(unsigned int)); + if (!dbuf->dgram_len) goto fail4; - dbuf->dgram_len = calloc(dgram_count, sizeof(ssize_t)); - if (!dbuf->dgram_len) goto fail5; + dbuf->dgram_seq_numbers = calloc(dgram_slots, sizeof(unsigned int)); + if (!dbuf->dgram_seq_numbers) goto fail5; - dbuf->dgram_ordered_seq_numbers = calloc(dgram_count, sizeof(struct uint_pair)); + dbuf->dgram_ordered_seq_numbers = calloc(dgram_slots, sizeof(struct uint_pair)); if (!dbuf->dgram_ordered_seq_numbers) goto fail6; - dbuf->buf = calloc(dgram_count, dgram_max_size); + dbuf->buf = calloc(dgram_slots, dgram_max_size); if (!dbuf->buf) goto fail7; return dbuf; fail7: free(dbuf->dgram_ordered_seq_numbers); -fail6: free(dbuf->dgram_len); -fail5: free(dbuf->dgram_seq_numbers); +fail6: free(dbuf->dgram_seq_numbers); +fail5: free(dbuf->dgram_len); fail4: free(dbuf->msgs); -fail3: free(dbuf->write_iovecs); -fail2: free(dbuf->recv_iovecs); +fail3: free(dbuf->iov_write); +fail2: free(dbuf->iov_recv); fail1: free(dbuf); -fail0: return 0; +fail0: return NULL; } void dgrambuf_free(dgrambuf_t *dbuf) { if (dbuf && *dbuf) { free((*dbuf)->buf); free((*dbuf)->dgram_ordered_seq_numbers); - free((*dbuf)->dgram_len); free((*dbuf)->dgram_seq_numbers); + free((*dbuf)->dgram_len); free((*dbuf)->msgs); - free((*dbuf)->write_iovecs); - free((*dbuf)->recv_iovecs); + free((*dbuf)->iov_write); + free((*dbuf)->iov_recv); free(*dbuf); } *dbuf = NULL; -- cgit v1.2.3