/**
* Reads and returns a templated array encoded in the Watchman binary protocol
* format, starting at `ptr` and finishing at or before `end`
*
* Templated arrays are arrays of hashes which have repetitive key information
* pulled out into a separate "headers" prefix.
*
* @see https://github.com/facebook/watchman/blob/master/BSER.markdown
*/
VALUE watchman_load_template(char **ptr, char *end) {
int64_t header_items_count, i, row_count;
VALUE array, hash, header, key, value;
*ptr += sizeof(int8_t); // caller has already verified the marker
// process template header array
header_items_count = watchman_load_array_header(ptr, end);
header = rb_ary_new2(header_items_count);
for (i = 0; i < header_items_count; i++) {
rb_ary_push(header, watchman_load_string(ptr, end));
}
// process row items
row_count = watchman_load_int(ptr, end);
array = rb_ary_new2(header_items_count);
while (row_count--) {
hash = rb_hash_new();
for (i = 0; i < header_items_count; i++) {
if (*ptr >= end) {
rb_raise(rb_eArgError, "unexpected end of input");
}
if (*ptr[0] == WATCHMAN_SKIP_MARKER) {
*ptr += sizeof(uint8_t);
} else {
value = watchman_load(ptr, end);
key = rb_ary_entry(header, i);
rb_hash_aset(hash, key, value);
}
}
rb_ary_push(array, hash);
}
return array;
}
/**
* Reads and returns an array encoded in the Watchman binary protocol format,
* starting at `ptr` and finishing at or before `end`
*/
VALUE watchman_load_array(char **ptr, char *end) {
int64_t count, i;
VALUE array;
count = watchman_load_array_header(ptr, end);
array = rb_ary_new2(count);
for (i = 0; i < count; i++) {
rb_ary_push(array, watchman_load(ptr, end));
}
return array;
}
/**
* CommandT::Watchman::Utils.load(serialized)
*
* Converts the binary object, `serialized`, from the Watchman binary protocol
* format into a normal Ruby object.
*/
VALUE CommandTWatchmanUtils_load(VALUE self, VALUE serialized) {
char *ptr, *end;
long len;
uint64_t payload_size;
VALUE loaded;
serialized = StringValue(serialized);
len = RSTRING_LEN(serialized);
ptr = RSTRING_PTR(serialized);
end = ptr + len;
// expect at least the binary marker and a int8_t length counter
if ((size_t)len < sizeof(WATCHMAN_BINARY_MARKER) - 1 + sizeof(int8_t) * 2) {
rb_raise(rb_eArgError, "undersized header");
}
if (memcmp(ptr, WATCHMAN_BINARY_MARKER, sizeof(WATCHMAN_BINARY_MARKER) - 1)) {
rb_raise(rb_eArgError, "missing binary marker");
}
// get size marker
ptr += sizeof(WATCHMAN_BINARY_MARKER) - 1;
payload_size = watchman_load_int(&ptr, end);
if (!payload_size) {
rb_raise(rb_eArgError, "empty payload");
}
// sanity check length
if (ptr + payload_size != end) {
rb_raise(
rb_eArgError,
"payload size mismatch (%lu)",
(unsigned long)(end - (ptr + payload_size))
);
}
loaded = watchman_load(&ptr, end);
// one more sanity check
if (ptr != end) {
rb_raise(
rb_eArgError,
"payload termination mismatch (%lu)",
(unsigned long)(end - ptr)
);
}
return loaded;
}
/**
* Reads and returns a hash encoded in the Watchman binary protocol format,
* starting at `ptr` and finishing at or before `end`
*/
VALUE watchman_load_hash(char **ptr, char *end) {
int64_t count, i;
VALUE hash, key, value;
*ptr += sizeof(int8_t); // caller has already verified the marker
// expect a count
if (*ptr + sizeof(int8_t) * 2 > end) {
rb_raise(rb_eArgError, "incomplete hash header");
}
count = watchman_load_int(ptr, end);
hash = rb_hash_new();
for (i = 0; i < count; i++) {
key = watchman_load_string(ptr, end);
value = watchman_load(ptr, end);
rb_hash_aset(hash, key, value);
}
return hash;
}
/**
* CommandT::Watchman::Utils.query(query, socket)
*
* Converts `query`, a Watchman query comprising Ruby objects, into the Watchman
* binary protocol format, transmits it over socket, and unserializes and
* returns the result.
*/
VALUE CommandTWatchmanUtils_query(VALUE self, VALUE query, VALUE socket) {
char *payload;
int fileno, flags;
int8_t peek[WATCHMAN_PEEK_BUFFER_SIZE];
int8_t sizes[] = { 0, 0, 0, 1, 2, 4, 8 };
int8_t sizes_idx;
int8_t *pdu_size_ptr;
int64_t payload_size;
long query_len;
ssize_t peek_size, sent, received;
void *buffer;
VALUE loaded, serialized;
fileno = NUM2INT(rb_funcall(socket, rb_intern("fileno"), 0));
// do blocking I/O to simplify the following logic
flags = fcntl(fileno, F_GETFL);
if (fcntl(fileno, F_SETFL, flags & ~O_NONBLOCK) == -1) {
rb_raise(rb_eRuntimeError, "unable to clear O_NONBLOCK flag");
}
// send the message
serialized = CommandTWatchmanUtils_dump(self, query);
query_len = RSTRING_LEN(serialized);
sent = send(fileno, RSTRING_PTR(serialized), query_len, 0);
if (sent == -1) {
watchman_raise_system_call_error(errno);
} else if (sent != query_len) {
rb_raise(rb_eRuntimeError, "expected to send %ld bytes but sent %ld",
query_len, sent);
}
// sniff to see how large the header is
received = recv(fileno, peek, WATCHMAN_SNIFF_BUFFER_SIZE, MSG_PEEK | MSG_WAITALL);
if (received == -1) {
watchman_raise_system_call_error(errno);
} else if (received != WATCHMAN_SNIFF_BUFFER_SIZE) {
rb_raise(rb_eRuntimeError, "failed to sniff PDU header");
}
// peek at size of PDU
sizes_idx = peek[sizeof(WATCHMAN_BINARY_MARKER) - 1];
if (sizes_idx < WATCHMAN_INT8_MARKER || sizes_idx > WATCHMAN_INT64_MARKER) {
rb_raise(rb_eRuntimeError, "bad PDU size marker");
}
peek_size = sizeof(WATCHMAN_BINARY_MARKER) - 1 + sizeof(int8_t) +
sizes[sizes_idx];
received = recv(fileno, peek, peek_size, MSG_PEEK);
if (received == -1) {
watchman_raise_system_call_error(errno);
} else if (received != peek_size) {
rb_raise(rb_eRuntimeError, "failed to peek at PDU header");
}
pdu_size_ptr = peek + sizeof(WATCHMAN_BINARY_MARKER) - sizeof(int8_t);
payload_size =
peek_size +
watchman_load_int((char **)&pdu_size_ptr, (char *)peek + peek_size);
// actually read the PDU
buffer = xmalloc(payload_size);
if (!buffer) {
rb_raise(
rb_eNoMemError,
"failed to allocate %lld bytes",
(long long int)payload_size
);
}
received = recv(fileno, buffer, payload_size, MSG_WAITALL);
if (received == -1) {
watchman_raise_system_call_error(errno);
} else if (received != payload_size) {
rb_raise(rb_eRuntimeError, "failed to load PDU");
}
payload = (char *)buffer + peek_size;
loaded = watchman_load(&payload, payload + payload_size);
free(buffer);
return loaded;
}
/**
* RubyWatchman.query(query, socket)
*
* Converts `query`, a Watchman query comprising Ruby objects, into the Watchman
* binary protocol format, transmits it over socket, and unserializes and
* returns the result.
*/
VALUE RubyWatchman_query(VALUE self, VALUE query, VALUE socket) {
VALUE error = Qnil;
VALUE errorClass = Qnil;
VALUE loaded = Qnil;
void *buffer = NULL;
int fileno = NUM2INT(rb_funcall(socket, rb_intern("fileno"), 0));
// do blocking I/O to simplify the following logic
int flags = fcntl(fileno, F_GETFL);
if (
!(flags & O_NONBLOCK) &&
fcntl(fileno, F_SETFL, flags & ~O_NONBLOCK) == -1
) {
error = rb_str_new2("unable to clear O_NONBLOCK flag");
goto cleanup;
}
// send the message
VALUE serialized = RubyWatchman_dump(self, query);
long query_len = RSTRING_LEN(serialized);
ssize_t sent = send(fileno, RSTRING_PTR(serialized), query_len, 0);
if (sent == -1) {
goto system_call_fail;
} else if (sent != query_len) {
error = rb_str_new2("sent byte count mismatch");
goto cleanup;
}
// sniff to see how large the header is
int8_t peek[WATCHMAN_PEEK_BUFFER_SIZE];
ssize_t received =
recv(fileno, peek, WATCHMAN_SNIFF_BUFFER_SIZE, MSG_PEEK | MSG_WAITALL);
if (received == -1) {
goto system_call_fail;
} else if (received != WATCHMAN_SNIFF_BUFFER_SIZE) {
error = rb_str_new2("failed to sniff PDU header");
goto cleanup;
}
// peek at size of PDU
int8_t sizes[] = { 0, 0, 0, 1, 2, 4, 8 };
int8_t sizes_idx = peek[sizeof(WATCHMAN_BINARY_MARKER) - 1];
if (sizes_idx < WATCHMAN_INT8_MARKER || sizes_idx > WATCHMAN_INT64_MARKER) {
error = rb_str_new2("bad PDU size marker");
goto cleanup;
}
ssize_t peek_size = sizeof(WATCHMAN_BINARY_MARKER) - 1 + sizeof(int8_t) +
sizes[sizes_idx];
received = recv(fileno, peek, peek_size, MSG_PEEK);
if (received == -1) {
goto system_call_fail;
} else if (received != peek_size) {
error = rb_str_new2("failed to peek at PDU header");
goto cleanup;
}
int8_t *pdu_size_ptr =
peek + sizeof(WATCHMAN_BINARY_MARKER) - sizeof(int8_t);
int64_t payload_size =
peek_size +
watchman_load_int((char **)&pdu_size_ptr, (char *)peek + peek_size);
// actually read the PDU
buffer = xmalloc(payload_size);
if (!buffer) {
errorClass = rb_eNoMemError;
error = rb_str_new2("failed to allocate");
goto cleanup;
}
received = recv(fileno, buffer, payload_size, MSG_WAITALL);
if (received == -1) {
goto system_call_fail;
} else if (received != payload_size) {
error = rb_str_new2("failed to load PDU");
goto cleanup;
}
if (!(flags & O_NONBLOCK) && fcntl(fileno, F_SETFL, flags) == -1) {
error = rb_str_new2("unable to restore fnctl flags");
goto cleanup;
}
char *payload = buffer + peek_size;
loaded = watchman_load(&payload, payload + payload_size);
goto cleanup;
system_call_fail:
errorClass = rb_eSystemCallError;
error = INT2FIX(errno);
cleanup:
if (buffer) {
xfree(buffer);
}
if (!(flags & O_NONBLOCK) && fcntl(fileno, F_SETFL, flags) == -1) {
rb_raise(rb_eRuntimeError, "unable to restore fnctl flags");
}
if (NIL_P(errorClass)) {
errorClass = rb_eRuntimeError;
}
if (!NIL_P(error)) {
rb_exc_raise(rb_class_new_instance(1, &error, errorClass));
}
return loaded;
}
