[Libguestfs] [nbdkit PATCH v3 07/16] server: Manage contexts by backend, not int

Minor refactoring, since all callers already have a struct backend available when manipulating a context associated with a connection. --- server/internal.h | 21 +++------- server/backend.c | 62 ++++++++++++++-------------- server/connections.c | 17 +++++++- server/filters.c | 2 +- server/protocol-handshake-newstyle.c | 2 +- server/protocol-handshake.c | 2 +- 6 files changed, 55 insertions(+), 51 deletions(-) diff --git a/server/internal.h b/server/internal.h index ff543200..28c65629 100644 --- a/server/internal.h +++ b/server/internal.h @@ -195,10 +195,6 @@ typedef void (*connection_close_function) (void); /* struct context stores data per connection and backend. Primarily * this is the filter or plugin handle, but other state is also stored * here. - * - * Use get_context (conn, 0) to return the struct context for the - * plugin, and get_context (conn, b->i) to return the struct context for - * the i'th backend (if b->i >= 1 then for a filter). */ enum { HANDLE_OPEN = 1, /* Set if .open passed, so .close is needed */ @@ -257,18 +253,11 @@ struct connection { connection_close_function close; }; -static inline struct context * -get_context (struct connection *conn, int i) -{ - return conn->contexts[i]; -} - -static inline void -set_context (struct connection *conn, int i, struct context *context) -{ - conn->contexts[i] = context; -} - +extern struct context *get_context (struct connection *conn, struct backend *b) + __attribute__((__nonnull__(1))); +extern void set_context (struct connection *conn, struct backend *b, + struct context *c) + __attribute__((__nonnull__(1))); extern void handle_single_connection (int sockin, int sockout); extern int connection_get_status (void); extern int connection_set_status (int value); diff --git a/server/backend.c b/server/backend.c index e89f0ab4..c382c71d 100644 --- a/server/backend.c +++ b/server/backend.c @@ -163,7 +163,7 @@ backend_list_exports (struct backend *b, int readonly, struct nbdkit_exports *exports) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); size_t count; controlpath_debug ("%s: list_exports readonly=%d tls=%d", @@ -186,7 +186,7 @@ const char * backend_default_export (struct backend *b, int readonly) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); const char *s; controlpath_debug ("%s: default_export readonly=%d tls=%d", @@ -272,7 +272,7 @@ int backend_prepare (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); assert (c->handle); assert ((c->state & (HANDLE_OPEN | HANDLE_CONNECTED)) == HANDLE_OPEN); @@ -281,7 +281,7 @@ backend_prepare (struct backend *b) * plugin, similar to typical .open order. But remember that * a filter may skip opening its backend. */ - if (b->i && get_context (conn, b->i-1) != NULL && + if (b->i && get_context (conn, b->next) != NULL && backend_prepare (b->next) == -1) return -1; @@ -297,7 +297,7 @@ int backend_finalize (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); /* Call these in reverse order to .prepare above, starting from the * filter furthest away from the plugin, and matching .close order. @@ -316,7 +316,7 @@ backend_finalize (struct backend *b) } } - if (b->i && get_context (conn, b->i-1)) + if (b->i && get_context (conn, b->next)) return backend_finalize (b->next); return 0; } @@ -325,7 +325,7 @@ void backend_close (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); /* outer-to-inner order, opposite .open */ assert (c->handle); @@ -333,8 +333,8 @@ backend_close (struct backend *b) controlpath_debug ("%s: close", b->name); b->close (b, c->handle); free (c); - set_context (conn, b->i, NULL); - if (b->i && get_context (conn, b->i-1)) + set_context (conn, b, NULL); + if (b->i && get_context (conn, b->next)) backend_close (b->next); } @@ -342,7 +342,7 @@ bool backend_valid_range (struct backend *b, uint64_t offset, uint32_t count) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); assert (c->exportsize <= INT64_MAX); /* Guaranteed by negotiation phase */ return count > 0 && offset <= c->exportsize && @@ -360,7 +360,7 @@ backend_reopen (struct backend *b, int readonly, const char *exportname) controlpath_debug ("%s: reopen readonly=%d exportname=\"%s\"", b->name, readonly, exportname); - if (get_context (conn, b->i)) { + if (get_context (conn, b)) { if (backend_finalize (b) == -1) return -1; backend_close (b); @@ -368,7 +368,7 @@ backend_reopen (struct backend *b, int readonly, const char *exportname) h = backend_open (b, readonly, exportname); if (h == NULL) return -1; - set_context (conn, b->i, h); + set_context (conn, b, h); if (backend_prepare (b) == -1) { backend_finalize (b); backend_close (b); @@ -383,7 +383,7 @@ const char * backend_export_description (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); const char *s; controlpath_debug ("%s: export_description", b->name); @@ -405,7 +405,7 @@ int64_t backend_get_size (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); assert (c->handle && (c->state & HANDLE_CONNECTED)); if (c->exportsize == -1) { @@ -419,7 +419,7 @@ int backend_can_write (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); assert (c->handle && (c->state & HANDLE_CONNECTED)); if (c->can_write == -1) { @@ -433,7 +433,7 @@ int backend_can_flush (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); assert (c->handle && (c->state & HANDLE_CONNECTED)); if (c->can_flush == -1) { @@ -447,7 +447,7 @@ int backend_is_rotational (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); assert (c->handle && (c->state & HANDLE_CONNECTED)); if (c->is_rotational == -1) { @@ -461,7 +461,7 @@ int backend_can_trim (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); int r; assert (c->handle && (c->state & HANDLE_CONNECTED)); @@ -481,7 +481,7 @@ int backend_can_zero (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); int r; assert (c->handle && (c->state & HANDLE_CONNECTED)); @@ -501,7 +501,7 @@ int backend_can_fast_zero (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); int r; assert (c->handle && (c->state & HANDLE_CONNECTED)); @@ -521,7 +521,7 @@ int backend_can_extents (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); assert (c->handle && (c->state & HANDLE_CONNECTED)); if (c->can_extents == -1) { @@ -535,7 +535,7 @@ int backend_can_fua (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); int r; assert (c->handle && (c->state & HANDLE_CONNECTED)); @@ -555,7 +555,7 @@ int backend_can_multi_conn (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); assert (c->handle && (c->state & HANDLE_CONNECTED)); if (c->can_multi_conn == -1) { @@ -569,7 +569,7 @@ int backend_can_cache (struct backend *b) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); assert (c->handle && (c->state & HANDLE_CONNECTED)); if (c->can_cache == -1) { @@ -585,7 +585,7 @@ backend_pread (struct backend *b, uint32_t flags, int *err) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); int r; assert (c->handle && (c->state & HANDLE_CONNECTED)); @@ -606,7 +606,7 @@ backend_pwrite (struct backend *b, uint32_t flags, int *err) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); bool fua = !!(flags & NBDKIT_FLAG_FUA); int r; @@ -630,7 +630,7 @@ backend_flush (struct backend *b, uint32_t flags, int *err) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); int r; assert (c->handle && (c->state & HANDLE_CONNECTED)); @@ -650,7 +650,7 @@ backend_trim (struct backend *b, int *err) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); bool fua = !!(flags & NBDKIT_FLAG_FUA); int r; @@ -676,7 +676,7 @@ backend_zero (struct backend *b, int *err) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); bool fua = !!(flags & NBDKIT_FLAG_FUA); bool fast = !!(flags & NBDKIT_FLAG_FAST_ZERO); int r; @@ -711,7 +711,7 @@ backend_extents (struct backend *b, struct nbdkit_extents *extents, int *err) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); int r; assert (c->handle && (c->state & HANDLE_CONNECTED)); @@ -742,7 +742,7 @@ backend_cache (struct backend *b, uint32_t flags, int *err) { GET_CONN; - struct context *c = get_context (conn, b->i); + struct context *c = get_context (conn, b); int r; assert (c->handle && (c->state & HANDLE_CONNECTED)); diff --git a/server/connections.c b/server/connections.c index e3fdc649..0115875b 100644 --- a/server/connections.c +++ b/server/connections.c @@ -360,7 +360,7 @@ free_connection (struct connection *conn) */ if (!quit) { lock_request (); - if (get_context (conn, top->i)) + if (get_context (conn, top)) backend_close (top); unlock_request (); } @@ -499,3 +499,18 @@ raw_close (void) if (conn->sockout >= 0 && conn->sockin != conn->sockout) closesocket (conn->sockout); } + +struct context * +get_context (struct connection *conn, struct backend *b) +{ + struct context *c = conn->contexts[b->i]; + assert (!c || c->b == b); + return c; +} + +void +set_context (struct connection *conn, struct backend *b, struct context *c) +{ + assert (!c || c->b == b); + conn->contexts[b->i] = c; +} diff --git a/server/filters.c b/server/filters.c index dde36306..fb123670 100644 --- a/server/filters.c +++ b/server/filters.c @@ -268,7 +268,7 @@ next_open (struct backend *b, int readonly, const char *exportname) if (c == NULL) return -1; - set_context (conn, b->i, c); + set_context (conn, b, c); return 0; } diff --git a/server/protocol-handshake-newstyle.c b/server/protocol-handshake-newstyle.c index 015e7f9b..4bc802cc 100644 --- a/server/protocol-handshake-newstyle.c +++ b/server/protocol-handshake-newstyle.c @@ -567,7 +567,7 @@ negotiate_handshake_newstyle_options (void) */ if (finish_newstyle_options (&exportsize, &data[4], exportnamelen) == -1) { - if (get_context (conn, top->i)) { + if (get_context (conn, top)) { if (backend_finalize (top) == -1) return -1; backend_close (top); diff --git a/server/protocol-handshake.c b/server/protocol-handshake.c index 82e7e647..69f8b530 100644 --- a/server/protocol-handshake.c +++ b/server/protocol-handshake.c @@ -84,7 +84,7 @@ protocol_common_open (uint64_t *exportsize, uint16_t *flags, c = backend_open (top, read_only, exportname); if (c == NULL) return -1; - set_context (conn, top->i, c); + set_context (conn, top, c); /* Prepare (for filters), called just after open. */ if (backend_prepare (top) == -1) -- 2.30.1