* src/cuirass/base.scm (cancel-old-builds): New procedure.

* bin/evaluate.in (main): 'build-things' replacement no longer calls 'exit'.

Fixes a bug whereby some fibers would get a SQLITE_BUSY exception while
accessing the database: see
<https://debbugs.gnu.org/cgi/bugreport.cgi?bug=30644#26>.

Suggested by Danny Milosavljevic <dannym@scratchpost.org>.

* src/cuirass/database.scm (wal-mode): Rename to...
(set-db-options): ... this.  Add call to 'sqlite-exec' for
'busy_timeout'.

* bin/cuirass.in (main): Add 'setvbuf' calls.

* src/cuirass/base.scm (with-store): Rewrite using 'unwind-protect'.
* src/cuirass/database.scm (with-database): Likewise.

* src/cuirass/utils.scm (unwind-protect): New macro.

Fixes a regression introduced in
f083282f, whereby we'd return 0 as the
timestamp for everything in /api/queue.

* src/cuirass/http.scm (build->hydra-build): Make 'finished?' a
Boolean.  Move 'bool->int' call in #:finished definition.

Previously, when an exception was raised from
'handle-build-event' (e.g., a "database is locked" error), we'd throw,
thereby leaving PORT open and we'd never read from it again.  Thus, the
corresponding 'guix-daemon' process would eventually get stuck in a
'write' call to that socket, and its build processes would stall.

* src/cuirass/base.scm (exception-reporter): New procedure.
(spawn-builds): Use it.

Fixes <https://bugs.gnu.org/30618>.
Reported by Andreas Enge <andreas@enge.fr>.

* bin/evaluate.in (fill-job): Remove.
(main): Remove 'database' command-line argument.  Remove DB and its
uses.  Write an (evaluation EVAL JOBS) sexp.
* src/cuirass/base.scm (evaluate)[augment-job]: New procedure.
Use it.  Adjust to read (evaluation EVAL JOBS) sexp.  Call
'db-add-evaluation' and 'db-add-derivation'.

Fixes <https://bugs.gnu.org/30645>.
Reported by Andreas Enge <andreas@enge.fr>.

* src/cuirass/base.scm (spawn-builds): Fix TOTAL vs. COUNT mismatches.

* src/cuirass/http.scm (build->hydra-build): Set #:timestamp to
  #:stoptime when BUILD is finished.

* src/cuirass/database.scm (db-get-builds): Reindent.

* src/cuirass/database.scm (db-get-builds)[assqx-ref]: Rewrite with
'match'.

* src/cuirass/http.scm (request-parameters): Return the empty list when
QUERY is #f.

Fixes a regression introduced in
593cb7be.

* src/cuirass/http.scm (request-parameters): Fix fallback case in
'match' form.  Previously it would return a procedure in this case, as
returned by (const param), leading to a failure down the road in
'sqlite-bind-arguments' as could be seen by running tests/http.scm.

I've seen 'scandir' report #f once, even though that's theoretically
impossible.

* src/cuirass/logging.scm (log-monitoring-stats): Return '() if
'scandir' returns #f.

* src/cuirass/database.scm (db-get-builds): Fix grouping.

* src/cuirass/http.scm (request-parameters): Interpret id and nr parameters as
numbers.

* src/cuirass/database.scm (db-get-builds): Remove debugging output.
(db-get-build): Remove debugging output.

* src/cuirass/http.scm (url-handler): Convert build-id URL part to number.

* src/cuirass/database.scm (db-get-builds): Inline output selection.

* src/cuirass/database.scm (db-get-builds): Modify.
(db-get-build): Modify.

* Makefile.am (CLEANFILES): Add $(nodist_guilesite_DATA).

Previously it would be installed under cuirass/.

* Makefile.am (webmoduledir, webobjectdir): New variables.
(dist_pkgmodule_DATA): Remove src/web/server/fiberized.scm.
(dist_webmodule_DATA, nodist_webobject_DATA): New variables.
(CLEANFILES): Add $(nodist_webobject_DATA).

* src/cuirass/base.scm (clear-build-queue): New procedure.
* bin/cuirass.in (main): Call it.

* examples/random-jobs.scm (random-derivation): Add 'suffix' parameter
and honor it.
(make-random-jobs): Pass a non-empty suffix to 'random-derivation'.

* src/schema.sql: Add indices.

This reverts commit c47dfdf8.

Processing connections concurrently would require having separate
database handles.  See
<https://lists.gnu.org/archive/html/guix-devel/2018-02/msg00206.html>.

* src/cuirass/database.scm (db-add-derivation): Catch 'sqlite-error and
handle SQLITE_CONSTRAINT_PRIMARYKEY.
(SQLITE_CONSTRAINT_UNIQUE): New variable.
* tests/database.scm ("database")["db-add-derivation"]: Add extra call to
'db-add-derivation'.

Before that, 'run-server' would force sequential processing of client
requests one after another.

* src/cuirass/http.scm (run-cuirass-server): Rewrite to use its own loop
instead of 'run-server'.

* src/cuirass/utils.scm (%non-blocking): Forward exceptions to the
calling fiber.

That makes it safe from SQL injection.

* src/cuirass/database.scm (db-get-builds): Rewrite to use question
marks in SQL queries and binding through '%sqlite-exec'.
* tests/database.scm ("database")["db-get-builds"]: Exercise 'WHERE'
clauses.

The new macro automatically takes care of inserting question marks in
the SQL queries, which in turn guarantees that there are always as many
question marks and arguments.

* src/cuirass/database.scm (sqlite-exec): Rename to...
(%sqlite-exec): ... this.
(sqlite-exec/bind, sqlite-exec): New macros.
(assq-refs): Remove.
(db-add-specification): Use the new 'sqlite-exec' form.
(db-get-specifications): Correctly deal with REV or TAG being #f.
(db-add-derivation, db-get-derivation, db-add-evaluation)
(db-add-build, db-update-build-status!, db-get-outputs)
(db-get-build, db-get-stamp, db-add-stamp): Adjust to the new
'sqlite-exec' form.

* examples/random-jobs.scm (random-derivation): Tweak the computation of
SEED.  Actually use the new random state.

Previously any derivation not directly built by Cuirass would be
considered as failed because 'handle-build-event' wouldn't see any build
event.  Here we just make sure the build status recorded in the database
corresponds to reality.

* src/cuirass/base.scm (update-build-statuses!): New procedure.
(spawn-builds): Call it after 'build-derivations&'.

* src/cuirass/base.scm (build-packages)[register]: Make 'db-add-build' a
tail call.
Fix computation of 'outs'.

* examples/random-jobs.scm (make-job): Add '.' in #:job-name.

* src/cuirass/database.scm (db-update-build-status!): And "AND status != ?"
in SQL queries.
* tests/database.scm ("database")["db-update-build-status!"]: Add call
to 'db-update-build-status!'.

This is purely "defensive programming" since the default value for
'print-build-trace' is currently #t.

* src/cuirass/base.scm (with-store): Pass #:print-build-trace to
'set-build-options'.

Suggested by Danny Milosavljevic.

* src/cuirass/database.scm (sqlite-exec): Pass #:cache? to
'sqlite-prepare'.