Port Postgres egg to CHICKEN 65.0.0

This has quite a few changes due to the low-level nature of this code:
when the contents of a string get copied by C functions, we can't pass
it to arguments of the scheme-pointer type directly anymore.

Instead, strings are now wrapper objects which point to an internal
(NUL-terminated!) bytevector.  So not only do we have to extract this
bytevector and pass it to these C functions, but we also need to
calculate the string length excluding the NUL terminator.  This
creates a bit more branching in the code to get the thing to copy and
length.

The nice thing is that we no longer need to append NUL bytes to
strings in a few places.  Instead, we can just pass the raw bytevector
to the C functions, which means this should be rather faster now.

1 files changed, 69 insertions, 67 deletions

diff --git a/postgresql.scm b/postgresql.scm
index d2c4a03..801df81 100644
--- a/postgresql.scm
+++ b/postgresql.scm
@@ -55,6 +55,7 @@
   wait-for-notifications!)
 
  (import scheme
+         (scheme base)
          (chicken base)
          (chicken foreign)
          (chicken string)
@@ -63,7 +64,6 @@
          (chicken condition)
          (chicken format)
          (chicken gc)
-         (chicken blob)
          (chicken time)
          srfi-1
          srfi-4
@@ -145,13 +145,7 @@
 (define PQputCopyEnd (foreign-lambda int PQputCopyEnd pgconn* (const c-string)))
 (define PQgetCopyData (foreign-lambda int PQgetCopyData pgconn* (c-pointer (c-pointer char)) bool))
 
-(define memcpy (foreign-lambda c-pointer "C_memcpy" scheme-pointer c-pointer size_t))
-
-(define (srfi-4-vector? x) ; Copied from ##sys#srfi-4-vector? from 4.8.3
-  (and (##core#inline "C_blockp" x)
-       (##sys#generic-structure? x)
-       (memq (##sys#slot x 0)
-             '(u8vector u16vector s8vector s16vector u32vector s32vector f32vector f64vector))))
+(define memcpy (foreign-lambda c-pointer "C_memcpy" nonnull-scheme-pointer c-pointer size_t))
 
 ;; TODO: Create a real callback system?
 (foreign-declare "static void nullNoticeReceiver(void *arg, const PGresult *res){ }")
@@ -409,7 +403,7 @@
 (define default-type-unparsers
   (make-parameter
    `((,string? . ,(lambda (conn s) s))
-     (,u8vector? . ,(lambda (conn v) (u8vector->blob/shared v)))
+     (,bytevector? . ,(lambda (conn v) v))
      (,char? . ,(lambda (conn c) (string c)))
      (,boolean? . ,bool-unparser)
      (,number? . ,(lambda (conn n) (number->string n)))
@@ -462,7 +456,7 @@
   (let ((conn-fd (pgsql-connection->fd conn))
         (t ##sys#current-thread))
     (when delay (##sys#thread-block-for-timeout!
-                 t (+ (current-milliseconds) delay)))
+                 t (+ (current-process-milliseconds) delay)))
     (##sys#thread-block-for-i/o! t conn-fd in/out)
     (##sys#thread-yield!)))
 
@@ -504,23 +498,23 @@
       (cond-expand
         (has-connectdb-params
          (let ((len (length spec)))
-           ((foreign-lambda* pgconn* ((scheme-object cons) (scheme-pointer keybuf)
+           ((foreign-lambda* pgconn* ((scheme-object lst) (scheme-pointer keybuf)
                                       (scheme-pointer valbuf) (int len))
               "const char **key = (const char **)keybuf;"
               "const char **val = (const char **)valbuf;"
               "int i;"
-              "for (i=0; i < len; ++i,cons=C_u_i_cdr(cons)) {"
-              "    C_word kvpair = C_u_i_car(cons);"
-              "    key[i] = C_c_string(C_u_i_car(kvpair));"
-              "    val[i] = C_c_string(C_u_i_cdr(kvpair));"
+              "for (i=0; i < len; ++i, lst=C_u_i_cdr(lst)) {"
+              "    C_word kvpair = C_u_i_car(lst);"
+              "    key[i] = C_c_string(C_block_item(C_u_i_car(kvpair), 0));"
+              "    val[i] = C_c_string(C_block_item(C_u_i_cdr(kvpair), 0));"
               "}"
               "key[len] = NULL;"
               "val[len] = NULL;"
               "C_return(PQconnectStartParams(key, val, 0));")
-            (map (lambda (x) (cons (string-append (->string (car x)) "\x00")
-                                   (string-append (->string (cdr x)) "\x00"))) spec)
-            (make-blob (* (add1 len) (foreign-value "sizeof(char *)" int)))
-            (make-blob (* (add1 len) (foreign-value "sizeof(char *)" int)))
+            (map (lambda (x) (cons (->string (car x))
+                               (->string (cdr x)))) spec)
+            (make-bytevector (* (add1 len) (foreign-value "sizeof(char *)" int)))
+            (make-bytevector (* (add1 len) (foreign-value "sizeof(char *)" int)))
             len)))
         (else (PQconnectStart (alist->connection-spec spec))))))
 
@@ -670,13 +664,16 @@
                (fmt (PQfformat ptr column))
                (value (case fmt
                         ((0) (make-string len))
-                        ((1) (make-blob len))
+                        ((1) (make-bytevector len))
                         (else (postgresql-error
                                'internal 'value-at
                                (conc "Unknown column format type: " fmt)
-                               result column row raw)))))
-          (memcpy value (PQgetvalue-ptr ptr row column) len)
-          (if (or raw (blob? value))
+                               result column row raw))))
+               (raw-value (case fmt
+                            ((0) (##sys#slot value 0))
+                            ((1) value))))
+          (memcpy raw-value (PQgetvalue-ptr ptr row column) len)
+          (if (or raw (bytevector? value))
               value
               ((vector-ref (pg-result-value-parsers result) column) value))))))
 
@@ -982,16 +979,15 @@
   (let* ((params ;; Check all params and ensure they are proper pairs
           (map (lambda (p)
                  (let ((obj (if raw p (scheme-value->db-value conn p))))
-                   (cond ((string? obj) ; Convert to ASCIIZ
-                          (let* ((len (##sys#size obj))
-                                 (res (string-append obj "\x00")))
-                            (vector 0 len res)))
-                         ((blob? obj)
-                          (vector 1 (##sys#size obj) obj))
+                   (cond ((string? obj)
+                          ;; Extract the raw bytevector contents from the wrapped string object
+                          (vector 0 (string-length obj) (##sys#slot obj 0)))
+                         ((bytevector? obj)
+                          (vector 1 (bytevector-length obj) obj))
                          ((sql-null? obj) #f)
                          (else (postgresql-error
                                 'type 'query*
-                                (sprintf "Param value is not string, sql-null or blob: ~S" p)
+                                (sprintf "Param value is not string, sql-null or bytevector/u8vector: ~S" p)
                                 conn query params format)))))
                params))
          ;; It's a shame we need to traverse params twice (and again in C)...
@@ -1034,9 +1030,9 @@
           ((send-query (pg-connection-ptr conn) query-as-string (symbol? query)
                        len params
                        ;; We allocate here instead of in C to keep things simple
-                       (make-blob (* len (foreign-value "sizeof(char *)" int)))
-                       (make-blob (* len (foreign-value "sizeof(int)" int)))
-                       (make-blob (* len (foreign-value "sizeof(int)" int)))
+                       (make-bytevector (* len (foreign-value "sizeof(char *)" int)))
+                       (make-bytevector (* len (foreign-value "sizeof(int)" int)))
+                       (make-bytevector (* len (foreign-value "sizeof(int)" int)))
                        (symbol->format format))
            (get-last-result conn raw: raw))
           (else (postgresql-error 'i/o 'query*
@@ -1110,15 +1106,15 @@
 ;;;; COPY support
 ;;;;;;;;;;;;;;;;;;;;
 
-(define (put-copy-data conn data)
-  (let* ((data (cond
-                ((or (string? data) (blob? data)) data)
-                ((srfi-4-vector? data) (##sys#slot data 1))
-                (else (postgresql-error
-                       'type 'put-copy-data
-                       "Expected a blob, string or srfi-4 vector" conn data))))
-         (len (##sys#size data))
-         (conn-ptr (pg-connection-ptr conn)))
+(define (put-copy-data conn in-data)
+  (let* ((conn-ptr (pg-connection-ptr conn))
+         (data (cond ((string? in-data) (##sys#slot in-data 0))
+                     ((bytevector? in-data) in-data)
+                     (else (postgresql-error
+                            'type 'put-copy-data
+                            "Expected a bytevector/u8vector or string" conn in-data))))
+         (len (cond ((string? in-data) (string-length in-data))
+                     ((bytevector? in-data) (bytevector-length in-data)))))
     (let loop ((res (PQputCopyData conn-ptr data len)))
       (cond
        ((= res 0)
@@ -1158,14 +1154,17 @@
         (let ((res (PQgetCopyData conn-ptr (location buf) #t)))
           (cond
            ((> res 0)
-            (let ((value (case format
-                           ((text) (make-string res))
-                           ((binary) (make-blob res))
-                           (else (postgresql-error
-                                  'internal 'get-copy-data
-                                  (conc "Unknown column format type: " format)
-                                  conn)))))
-              (memcpy value buf res)
+            (let* ((value (case format
+                            ((text) (make-string res))
+                            ((binary) (make-bytevector res))
+                            (else (postgresql-error
+                                   'internal 'get-copy-data
+                                   (conc "Unknown column format type: " format)
+                                   conn))))
+                   (raw-value (case format
+                                ((text) (##sys#slot value 0))
+                                ((binary) value))))
+              (memcpy raw-value buf res)
               (free buf)
               value))
            ((= res 0)
@@ -1195,7 +1194,7 @@
            (buflen (add1 (* strlen 2)))
            (buffer (make-string buflen))
            (conn-ptr (pg-connection-ptr conn))
-           (size (%escape-string-conn conn-ptr buffer str strlen (location err))))
+           (size (%escape-string-conn conn-ptr (##sys#slot buffer 0) (##sys#slot str 0) strlen (location err))))
       (cond (err (postgresql-error 'internal 'escape-string
                                    (conc "String escaping failed. "
                                          (PQerrorMessage conn-ptr)) conn str))
@@ -1207,11 +1206,12 @@
     (has-escape-identifier
      (define %escape-ident
        (foreign-lambda c-string* PQescapeIdentifier pgconn* scheme-pointer size_t))
-     (or (%escape-ident (pg-connection-ptr conn) str (string-length str))
-         (postgresql-error 'internal 'quote-identifier
-                           (conc "Identifier escaping failed: "
-                                 (PQerrorMessage (pg-connection-ptr conn)))
-                           conn str)))
+     (let ((len (string-length str)))
+       (or (%escape-ident (pg-connection-ptr conn) (##sys#slot str 0) len)
+           (postgresql-error 'internal 'quote-identifier
+                             (conc "Identifier escaping failed: "
+                                   (PQerrorMessage (pg-connection-ptr conn)))
+                             conn str))))
     (else (postgresql-error 'unsupported-version 'quote-identifier
                             (conc "Please upgrade your PostgreSQL to 9.0 or later "
                                   "in order to be able to use quote-identifier!")
@@ -1222,18 +1222,20 @@
     (foreign-lambda (c-pointer unsigned-char) PQescapeByteaConn
       pgconn* scheme-pointer size_t (c-pointer size_t)))
   (let-location ((allocated size_t))
-    (let* ((data (cond ((or (string? obj) (blob? obj)) obj)
-                       ((srfi-4-vector? obj) (##sys#slot obj 1))
+    (let* ((conn-ptr (pg-connection-ptr conn))
+           (data (cond ((string? obj) (##sys#slot obj 0))
+                       ((bytevector? obj) obj)
                        (else (postgresql-error
                               'type 'escape-bytea
-                              "Expected string, blob or srfi-4 vector" obj))))
-           (conn-ptr (pg-connection-ptr conn))
+                              "Expected string or bytevector/u8vector" obj))))
+           (len (cond ((string? obj) (string-length obj))
+                      ((bytevector? obj) (bytevector-length obj))))
            (buf (%escape-bytea-conn
-                 conn-ptr data (##sys#size data) (location allocated))))
+                 conn-ptr data len (location allocated))))
       (if buf
           (let* ((string-length (sub1 allocated))
                  (result-string (make-string string-length)))
-            (memcpy result-string buf string-length)
+            (memcpy (##sys#slot result-string 0) buf string-length)
             (free buf)
             result-string)
           (postgresql-error
@@ -1244,13 +1246,13 @@
 (define (unescape-bytea str)
   (define %unescape-bytea
     (foreign-lambda (c-pointer unsigned-char) PQunescapeBytea c-string (c-pointer size_t)))
-  (let-location ((blob-length size_t))
-    (let ((buf (%unescape-bytea str (location blob-length))))
+  (let-location ((bv-length size_t))
+    (let ((buf (%unescape-bytea str (location bv-length))))
       (if buf 
-          (let ((result-blob (make-blob blob-length)))
-            (memcpy result-blob buf blob-length)
+          (let ((result-bv (make-bytevector bv-length)))
+            (memcpy result-bv buf bv-length)
             (free buf)
-            (blob->u8vector/shared result-blob))
+            result-bv)
           (postgresql-error 'internal 'unescape-bytea
                             "Byte array unescaping failed (out of memory?)" str)))))