Editing Technical specifications (section)

== 4. Pseudocode ==

<span id="primesmain"></span>
=== 4.1 primesmain ===

<pre>PROGRAM primesmain
  INPUT: command-line argument → commandline-args

  CALL primesui(&quot;start&quot;)
  IF ui-method-ok THEN
    LOG &quot;UI initialisation succeeded.&quot;
    LOG commandline-args
  ELSE
    DISPLAY emergency message on console
    STOP

  CASE commandline-args OF

    &quot;report&quot;:
      LOG &quot;Primes report generation starts.&quot;
      SET methods = &quot;report&quot;
      CALL primesgen(primes-session)       -- report flow

    &quot;generate&quot;:
      LOG &quot;Primes generation starts.&quot;
      SET methods = &quot;generate&quot;
      -- NOTE: CALL primesgen commented out in current source

    OTHER:
      LOG &quot;Bad parameter, program initialisation failed.&quot;
      CALL primesui(&quot;stop&quot;)
      STOP

  END CASE

  LOG &quot;Primes run complete, program stops.&quot;
  CALL primesui(&quot;stop&quot;)
  STOP
END PROGRAM</pre>
<span id="primesgen-report-path"></span>
=== 4.2 primesgen — report path ===

<pre>PROCEDURE report-path
  CALL primes-dal(&quot;connect&quot;)
  IF dal-method-ok THEN
    LOG &quot;Database initialisation succeeded.&quot;
  ELSE
    LOG &quot;Database initialisation failed.&quot;
    SET session-result = 1
    RETURN

  CALL primes-dal(&quot;cursor&quot;)           -- START TRANSACTION + OPEN primescursor
  IF dal-method-ok THEN
    LOG &quot;Cursor initialisation succeeded.&quot;
  ELSE
    LOG &quot;Cursor initialisation failed.&quot;
    SET session-result = 1
    RETURN

  FETCH first row via primes-dal(&quot;next-prime&quot;)
  IF fetch fails THEN
    LOG &quot;Fetch first row nok.&quot;
    SET dal-result = 1

  LOOP UNTIL session-method-eof
    SET u-sequence = primes-sequence
    SET u-number   = prime-number
    CALL primesui(&quot;write&quot;)            -- accumulate into print buffer
    CALL primes-dal(&quot;next-prime&quot;)     -- advance cursor
  END LOOP
END PROCEDURE</pre>
<span id="primesgen-generate-path"></span>
=== 4.3 primesgen — generate path ===

<pre>PROCEDURE generate-path
  CALL primes-dal(&quot;connect&quot;)
  IF dal-method-ok THEN
    SET test-divider   = 2
    SET old-ident      = 1
    SET test-number    = 3
    SET test-number-sqr = SQRT(3)
    LOG &quot;Database initialisation succeeded.&quot;
  ELSE
    LOG &quot;Database initialisation failed.&quot;
    SET session-result = 1
    RETURN

  LOOP UNTIL test-number = 999,999,999

    DIVIDE test-number BY test-divider → test-quot REMAINDER test-rest

    CASE OF
      test-rest = 0:
        -- test-number is composite; move to next candidate
        ADD 2 TO test-number
        SET test-number-sqr = SQRT(test-number)
        SET old-ident = 1
        FETCH divider[old-ident+1] via primes-dal(&quot;next-divider&quot;)

      test-divider &gt; test-number-sqr:
        -- no factor found up to sqrt; test-number is prime
        CALL primes-dal(&quot;write&quot;)      -- INSERT INTO primes
        CALL primesui(&quot;write&quot;)        -- add to print buffer
        ADD 2 TO test-number
        SET test-number-sqr = SQRT(test-number)
        SET old-ident = 1
        FETCH divider[old-ident+1] via primes-dal(&quot;next-divider&quot;)

      OTHERWISE:
        -- try next divider from DB
        FETCH divider[old-ident+1] via primes-dal(&quot;next-divider&quot;)
    END CASE

  END LOOP
END PROCEDURE</pre>
<span id="primes-dal"></span>
=== 4.4 primes (DAL) ===

<pre>PROGRAM primes
  LINKAGE: primes-dal

  CASE dal-methods OF
    &quot;connect&quot;:
      EXEC SQL CONNECT TO datasrc AS primes USER dbusr USING dbpwd
      IF SQLCODE = 0 THEN dal-result = 0 ELSE dal-result = 1

    &quot;cursor&quot;:
      EXEC SQL AT primes START TRANSACTION
      IF SQLCODE = 0 THEN
        EXEC SQL OPEN primescursor
        IF SQLCODE = 0 THEN dal-result = 0 ELSE dal-result = 1
      ELSE dal-result = 1

    &quot;next-prime&quot;:
      EXEC SQL FETCH primescursor INTO :primes-row
      IF SQLCODE = 0 THEN
        primes-sequence = r-ident
        prime-number    = r-prime
        dal-result = 0
      ELSE dal-result = 1

    &quot;next-divider&quot;:
      new-ident = old-ident + 1
      EXEC SQL SELECT prime INTO :test-divider
               FROM primes WHERE ident = :new-ident
      old-ident = new-ident

    &quot;write&quot;:
      EXEC SQL INSERT INTO primes (prime) VALUES (:prime)

    &quot;disconnect&quot;:
      EXEC SQL CONNECT RESET primes
      IF SQLCODE = 0 THEN dal-result = 0 ELSE dal-result = 1

    OTHER:
      dal-result = 1
  END CASE
  EXIT PROGRAM
END PROGRAM</pre>
<span id="primesui"></span>
=== 4.5 primesui ===

<pre>PROGRAM primesui
  LINKAGE: primes-ui

  CASE ui-methods OF
    &quot;start&quot;:
      OPEN OUTPUT fprinter (primes.prt)
      IF file-status = &quot;00&quot; THEN
        ui-method-result = 0
        primes-idx = 1
      ELSE
        ui-method-result = 1

    &quot;write&quot;:
      t-ident(primes-idx) = u-sequence
      t-prime(primes-idx) = u-number
      primes-idx = primes-idx + 1
      IF new-page THEN write heading + column header
      IF primes-idx = 7 THEN
        WRITE primes-table line to fprinter
        primes-idx = 1
      IF linage-counter = 53 THEN write footing, increment page

    &quot;log-message&quot;:
      DISPLAY process-message ON CONSOLE

    &quot;stop&quot;:
      LOOP writing zero rows UNTIL new-page   -- flush partial line
      CLOSE fprinter

  END CASE
  EXIT PROGRAM
END PROGRAM</pre>

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<span id="database-interface-specification"></span>