/*= -*- c-basic-offset: 4; indent-tabs-mode: nil; -*- * * librsync -- the library for network deltas * $Id: job.c,v 1.2 2004/09/10 11:18:45 zecke Exp $ * * Copyright (C) 2000, 2001 by Martin Pool * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public License * as published by the Free Software Foundation; either version 2.1 of * the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ /* | The hard, lifeless I covered up the | warm, pulsing It; protecting and | sheltering. */ /* * job.c -- Generic state-machine interface. The point of this is * that we need to be able to suspend and resume processing at any * point at which the buffers may block. We could do that using * setjmp or similar tricks, but this is probably simpler. * * TODO: We have a few functions to do with reading a netint, stashing * it somewhere, then moving into a different state. Is it worth * writing generic functions fo r that, or would it be too confusing? */ #include #include #include #include #include "rsync.h" #include "stream.h" #include "util.h" #include "sumset.h" #include "job.h" #include "trace.h" static const int rs_job_tag = 20010225; static rs_result rs_job_work(rs_job_t *job, rs_buffers_t *buffers); rs_job_t * rs_job_new(char const *job_name, rs_result (*statefn)(rs_job_t *)) { rs_job_t *job; job = rs_alloc_struct(rs_job_t); job->job_name = job_name; job->dogtag = rs_job_tag; job->statefn = statefn; job->stats.op = job_name; rs_trace("start %s job", job_name); return job; } void rs_job_check(rs_job_t *job) { assert(job->dogtag == rs_job_tag); } rs_result rs_job_free(rs_job_t *job) { rs_bzero(job, sizeof *job); free(job); return RS_DONE; } static rs_result rs_job_s_complete(rs_job_t *job) { job = job; rs_fatal("should not be reached"); return RS_INTERNAL_ERROR; } static rs_result rs_job_complete(rs_job_t *job, rs_result result) { rs_job_check(job); job->statefn = rs_job_s_complete; job->final_result = result; if (result != RS_DONE) { rs_error("%s job failed: %s", job->job_name, rs_strerror(result)); } else { rs_trace("%s job complete", job->job_name); } if (result == RS_DONE && !rs_tube_is_idle(job)) /* Processing is finished, but there is still some data * waiting to get into the output buffer. */ return RS_BLOCKED; else return result; } /** * \brief Run a ::rs_job_t state machine until it blocks * (::RS_BLOCKED), returns an error, or completes (::RS_COMPLETE). * * \return The ::rs_result that caused iteration to stop. * * \param ending True if there is no more data after what's in the * input buffer. The final block checksum will run across whatever's * in there, without trying to accumulate anything else. */ rs_result rs_job_iter(rs_job_t *job, rs_buffers_t *buffers) { rs_result result; rs_long_t orig_in, orig_out; orig_in = buffers->avail_in; orig_out = buffers->avail_out; result = rs_job_work(job, buffers); if (result == RS_BLOCKED || result == RS_DONE) if ((orig_in == buffers->avail_in) && (orig_out == buffers->avail_out) && orig_in && orig_out) { rs_log(RS_LOG_ERR, "internal error: job made no progress " "[orig_in=%.0f, orig_out=%.0f, final_in=%.0f, final_out=%.0f]", (double) orig_in, (double) orig_out, (double) buffers->avail_in, (double) buffers->avail_out); return RS_INTERNAL_ERROR; } return result; } static rs_result rs_job_work(rs_job_t *job, rs_buffers_t *buffers) { rs_result result; rs_job_check(job); if (!buffers) { rs_error("NULL buffer passed to rs_job_iter"); return RS_PARAM_ERROR; } job->stream = buffers; while (1) { result = rs_tube_catchup(job); if (result == RS_BLOCKED) return result; else if (result != RS_DONE) return rs_job_complete(job, result); if (job->statefn == rs_job_s_complete) { if (rs_tube_is_idle(job)) return RS_DONE; else return RS_BLOCKED; } else { result = job->statefn(job); if (result == RS_RUNNING) continue; else if (result == RS_BLOCKED) return result; else return rs_job_complete(job, result); } } /* TODO: Before returning, check that we actually made some * progress. If not, and we're not returning an error, this is a * bug. */ } /** * Return pointer to statistics accumulated about this job. */ const rs_stats_t * rs_job_statistics(rs_job_t *job) { return &job->stats; } int rs_job_input_is_ending(rs_job_t *job) { return job->stream->eof_in; } /** * Actively process a job, by making callbacks to fill and empty the * buffers until the job is done. */ rs_result rs_job_drive(rs_job_t *job, rs_buffers_t *buf, rs_driven_cb in_cb, void *in_opaque, rs_driven_cb out_cb, void *out_opaque) { rs_result result, iores; rs_bzero(buf, sizeof *buf); do { if (!buf->eof_in && in_cb) { iores = in_cb(job, buf, in_opaque); if (iores != RS_DONE) return iores; } result = rs_job_iter(job, buf); if (result != RS_DONE && result != RS_BLOCKED) return result; if (out_cb) { iores = (out_cb)(job, buf, out_opaque); if (iores != RS_DONE) return iores; } } while (result != RS_DONE); return result; }