Making Perl interface to PARI-2.0

[Ilya Zakharevich <ilya@math.ohio-state.edu>]

I started a remake of Math::PARI Perl's module for version 2.0.  Some of
the parts are working already (I released version 0.95_00 today, should 
propagate soon to CPAN: http://www.perl.com/CPAN/authors/ILYAZ/modules).

Here are the PARI problems I encountered:

Corrected, -p1-patch at the end:

a)  plotgnuplot.c had warnings (and no init segment, see `f').

b)  install() installs at the head of the chain, but findentry() 
    expects that the installed by foreighAutoload() entry goes into the
    end of the chain.  I changed the signature of foreighAutoload() to
    return entree*, thus made this problem disappear.

c)  err_recover() was flush()ing before giving the caller the possibility 
    to die().

d)  p-adic print was outputting extra space: bruteall() was overwriting 
    the old value of sp.

e)  fordiv() changed signature without a change to numeric interface,
    or the string signature.  I corrected the string signature.

f)  x86 assembler was putting overhead and hiremainder in uninit segment.
    The resulting object file had no init segment, so IBM linker was 
    skipping it (I was told that this is not a bug: allowed by standards).
    I special-cased it for the particular compiler and linking options.

g)  Moreover, OMF compile under EMX (necessary to get a full-feature DLL)
    has no underscores, but takes BSD syntax.  Again, I special-cased it.

h)  Gnuplot.h had a typo.

Not corrected:

1)  init_opts declared in gp/gp.h.  The idea of macros INIT_JMP_on and 
    friends was to make the switching accessible to the caller of PARI.

2)  wrong dependence for kernel0.o in none/Makefile.SH.

3)  changevalue() and installep() are statics, but they are important
    interfaces.

4)  numvar() disappeared altogether.

5)  GP function matinvr() disappeared without a trace.

6)  Instead of using __OPTIMIZE__ for switching inlining (ouch!!!), 
    Configure should check for -g in CFLAGS, and specify USE_INLINES macro.

7)  coinit() assumes that a long can be put in 9 chars ?!  (Some more around.)

8)  sum() and prod() have the same numeric interface, but different string
    interfaces.  -  This stops the translator dead.

9)  We need an additional output arg to hashvalue(): where parsing ended.
    This would simplify the usage of this function, and will make the life
    of interfacer to PARI simpler.

Enjoy,
Ilya

--- ./src/language/anal.c~	Thu Jul 23 08:40:30 1998
+++ ./src/language/anal.c	Fri Sep 11 19:54:22 1998
@@ -1536,12 +1536,7 @@ findentry(char *name, long len, entree *
     if (!strncmp(ep->name, name, len) && !(ep->name)[len]) return ep;
 
   if (foreignAutoload) /* Try to autoload. */
-    if (foreignAutoload(name, len))
-    {
-      for (ep = ep1; ep; ep = ep->next)
-        if (!strncmp(ep->name, name, len) && !(ep->name)[len]) return ep;
-      err(talker,"foreignAutoload reported success, but installed nothing");
-    }
+    return foreignAutoload(name, len);
   return NULL; /* not found */
 }
 
--- ./src/language/es.c~	Wed Sep  9 22:11:50 1998
+++ ./src/language/es.c	Fri Sep 11 21:38:22 1998
@@ -1668,9 +1668,14 @@ texi(GEN g, long nosign)
 void
 bruteall(GEN g, char f, long d, long flag)
 {
-  long av=avma; sp = flag? &wr_space: &no_space;
+  long av=avma; 
+  void (*oldsp)();
+
+  oldsp = sp;
+  sp = flag? &wr_space: &no_space;
   format = f; decimals = d;
   bruti(changevar(g,polvar),0); avma=av;
+  sp = oldsp;
 }
 
 void
--- ./src/language/init.c~	Thu Jul 30 08:47:38 1998
+++ ./src/language/init.c	Fri Sep 11 21:12:30 1998
@@ -38,7 +38,7 @@ ulong   top, bot, avma, memused;
 void *foreignHandler; 	              /* Handler for foreign commands.   */
 char foreignExprSwitch = 3; 	      /* Just some unprobable char.      */
 GEN  (*foreignExprHandler)(char*);    /* Handler for foreign expressions.*/
-long (*foreignAutoload)(char*, long); /* Autoloader                      */
+entree * (*foreignAutoload)(char*, long); /* Autoloader                      */
 void (*foreignFuncFree)(entree *);    /* How to free external entree.    */
 
 GEN  (*gp_history_fun)(long, long, char *, char *);
@@ -597,8 +597,9 @@ void
 err_recover(long numerr)
 {
   outfile=stdout; errfile=stderr;
-  fprintferr("\n"); flusherr();
+  fprintferr("\n");
   if (pariErr->die) pariErr->die();
+  flusherr();
   if (environnement)  
   { 
    /* wait till recover() is done before allocating a new stack.
@@ -1345,7 +1346,7 @@ entree functions_basic[]={
 {"fibonacci",11,(void*)fibo,4,"L"},
 {"floor",1,(void*)gfloor,2,"G"},
 {"for",83,(void*)forpari,11,"vV=GGI"},
-{"fordiv",84,(void*)fordiv,11,"vGVI"},
+{"fordiv",84,(void*)fordiv,11,"GVI"},
 {"forprime",83,(void*)forprime,11,"vV=GGI"},
 {"forstep",86,(void*)forstep,11,"vV=GGGI"},
 {"forvec",87,(void*)forvec,11,"vV=GID0,L,"},
--- ./src/kernel/ix86/l0asm.c~	Thu Jul 23 08:40:30 1998
+++ ./src/kernel/ix86/l0asm.c	Fri Sep 11 16:16:40 1998
@@ -28,6 +28,12 @@
 
 #include "l0asm.h"
 
+#if defined(__EMX__) && defined(__NO_AOUT) /* No underscores, rest as is */
+#   undef C
+#   define C(entrypoint) /**/entrypoint
+#endif
+
+
 #undef ALIGN
 #ifdef _MSC_VER
   #define ALIGN
@@ -59,8 +65,19 @@ unsigned long overflow;
 unsigned long hiremainder;
 #else
 #ifdef BSD_SYNTAX
+#  if defined(__EMX__) && defined(__NO_AOUT) /* Otherwise IBM linker will
+					        ignore this module */
+.data
+.align 2
+C(overflow):
+    .long 0
+C(hiremainder):
+    .long 0
+.text
+#  else
 .comm C(overflow),4
 .comm C(hiremainder),4
+#  endif
 #endif
 #ifdef ELF_SYNTAX
 .comm C(overflow),4,4
--- ./src/graph/Gnuplot.h~	Wed Sep  9 22:33:06 1998
+++ ./src/graph/Gnuplot.h	Fri Sep 11 04:14:40 1998
@@ -278,7 +278,7 @@ static struct termentry dummy_term_tbl[]
 	  UNKNOWN_null, UNKNOWN_null, UNKNOWN_null, UNKNOWN_null, UNKNOWN_null, 
 	  UNKNOWN_null, UNKNOWN_null, UNKNOWN_null,
      UNKNOWN_null, UNKNOWN_null, UNKNOWN_null, UNKNOWN_null, UNKNOWN_null, 0,
-	, UNKNOWN_null, UNKNOWN_null, UNKNOWN_null, UNKNOWN_null},
+	  UNKNOWN_null, UNKNOWN_null, UNKNOWN_null, UNKNOWN_null},
 };
 static struct termentry *my_term_tbl = dummy_term_tbl;
 
--- ./src/graph/plotgnuplot.c~	Wed Sep  9 22:33:06 1998
+++ ./src/graph/plotgnuplot.c	Fri Sep 11 14:53:44 1998
@@ -24,9 +24,8 @@ void
 rectdraw0(long *w, long *x, long *y, long lw, long do_free)
 {
   long *ptx,*pty;
-  long n,i,j,x0,y0;
-  long a,b,ne, good;
-  char **texts;
+  long i,j,x0,y0;
+  long good;
   int point_type = -1, line_type = 0;
   PariRect *e;
   RectObj *p1;
--- ./src/graph/plotport.c~	Thu Jul 23 08:40:24 1998
+++ ./src/graph/plotport.c	Fri Sep 11 09:14:12 1998
@@ -16,7 +16,7 @@ void rectdraw0(long *w, long *x, long *y
 static void PARI_get_psplot();
 
 static long current_color[NUMRECT];
-PariRect **rectgraph;
+PariRect **rectgraph = NULL;
 PARI_plot pari_plot, pari_psplot;
 
 #define STRINGRECT (NUMRECT-2)