... still programming ...

src/boxes.c

@@ -1,4 +1,27 @@
+/*
+ *  File:             boxes.c
+ *  Date created:     March 18, 1999 (Thursday, 15:09h)
+ *  Author:           Thomas Jensen
+ *                    tsjensen@stud.informatik.uni-erlangen.de
+ *  Version:          $Id$
+ *  Language:         ANSI C
+ *  Platforms:        sunos5/sparc, for now
+ *  World Wide Web:   http://home.pages.de/~jensen/boxes/
+ *  Purpose:          Filter to draw boxes around input text.
+ *                    Intended for use with vim(1).
+ *  Remarks:          This is not a release.
+ *
+ *  Revision History:
+ *
+ *    $Log$
+ *    Revision 1.1  1999/03/18  15:09:17  tsjensen
+ *    Initial revision
+ *
+* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ */
 
+
+#include <limits.h>
 #include <locale.h>
 #include <stdarg.h>
 #include <stdlib.h>
@@ -11,6 +34,8 @@ extern int optind, opterr, optopt;
 
 extern FILE *yyin;                       /* lex input file */
 
+const char rcsid[] = "$Id$";
+
 char *yyfilename = NULL;                 /* file name of config file used */
 
 design_t *designs = NULL;                /* available box designs */
@@ -19,6 +44,24 @@ int design_idx = 0;                      /* anz_designs-1 */
 int anz_designs = 0;                     /* no of designs after parsing */
 
 
+char *shape_name[] = {
+    "NW", "NNW", "N", "NNE", "NE", "ENE", "E", "ESE",
+    "SE", "SSE", "S", "SSW", "SW", "WSW", "W", "WNW"
+};
+
+char *ofs_name[] =   {
+    "NW_NNW", "NNW_N", "N_NNE", "NNE_NE", "NE_ENE", "ENE_E", "E_ESE", "ESE_SE",
+    "SE_SSE", "SSE_S", "S_SSW", "SSW_SW", "SW_WSW", "WSW_W", "W_WNW", "WNW_NW"
+};
+
+shape_t north_side[SHAPES_PER_SIDE] = { NW, NNW, N, NNE, NE };  /* clockwise */
+shape_t  east_side[SHAPES_PER_SIDE] = { NE, ENE, E, ESE, SE };
+shape_t south_side[SHAPES_PER_SIDE] = { SE, SSE, S, SSW, SW };
+shape_t  west_side[SHAPES_PER_SIDE] = { SW, WSW, W, WNW, NW };
+shape_t corners[ANZ_CORNERS] = { NW, NE, SE, SW };
+shape_t *sides[] = { north_side, east_side, south_side, west_side };
+
+
 struct {                                 /* command line options */
     int l;                               /* list available designs */
 } opt;
@@ -44,6 +87,81 @@ int yyerror (const char *fmt, ...)
 
 
 
+shape_t *on_side (const shape_t shape1, const shape_t shape2)
+/*
+ *  Compute the side that *both* shapes are on.
+ *
+ *  RETURNS: pointer to a side list  on success
+ *           NULL                    on error (e.g. shape on different sides)
+ *
+* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ */
+{
+    int i, j, found;
+
+    for (i=0; i<ANZ_SIDES; ++i) {
+        found = 0;
+        for (j=0; j<SHAPES_PER_SIDE; ++j) {
+            if (sides[i][j] == shape1 || sides[i][j] == shape2)
+                ++found;
+            if (found > 1) {
+                switch (i) {
+                    case 0: return north_side;
+                    case 1: return east_side;
+                    case 2: return south_side;
+                    case 3: return west_side;
+                    default: return NULL;
+                }
+            }
+        }
+    }
+
+    return NULL;
+}
+
+
+
+int shape_distance (const shape_t s1, const shape_t s2)
+/*
+ *  Compute distance between two shapes which are located on the same side
+ *  of the box. E.g. shape_distance(NW,N) == 2.
+ *
+ *  RETURNS: distance in steps   if ok
+ *           -1                  on error
+ *
+* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ */
+{
+    int i;
+    int distance = -1;
+    shape_t *workside = on_side (s1, s2);
+
+    if (!workside) return -1;
+    if (s1 == s2) return 0;
+
+    for (i=0; i<SHAPES_PER_SIDE; ++i) {
+        if (workside[i] == s1 || workside[i] == s2) {
+            if (distance == -1)
+                distance = 0;
+            else if (distance > -1) {
+                ++distance;
+                break;
+            }
+        }
+        else {
+            if (distance > -1)
+                ++distance;
+        }
+    }
+
+    if (distance > 0 && distance < SHAPES_PER_SIDE)
+        return distance;
+    else
+        return -1;
+}
+
+
+
 void usage (FILE *st)
 {
     fprintf (st, "Usage: %s [options] [infile [outfile]]\n", PROJECT);
@@ -129,9 +247,47 @@ int process_commandline (int argc, char *argv[])
         }
     } while (oc != EOF);
 
+    /*
+     *  If no config file has been specified, try getting it from other
+     *  locations. (1) contents of BOXES environment variable (2) file
+     *  ~/.boxes. If neither file exists, complain and die.
+     */
     if (yyin == stdin) {
-        fprintf (stderr, "%s: Could not find config file\n", PROJECT);
-        return 1;
+        char *s = getenv ("BOXES");
+        if (s) {
+            f = fopen (s, "r");
+            if (f == NULL) {
+                fprintf (stderr, "%s: Couldn\'t open config file \'%s\' "
+                        "for input (taken from environment).\n", PROJECT, s);
+                return 1;
+            }
+            yyfilename = (char *) strdup (s);
+            yyin = f;
+        }
+        else {
+            char buf[PATH_MAX];              /* to build file name */
+            s = getenv ("HOME");
+            if (s) {
+                strncpy (buf, s, PATH_MAX);
+                buf[PATH_MAX-1-7] = '\0';    /* ensure space for /.boxes */
+                strcat (buf, "/.boxes");
+                f = fopen (buf, "r");
+                if (f) {
+                    yyfilename = (char *) strdup (buf);
+                    yyin = f;
+                }
+                else {
+                    fprintf (stderr, "%s: Could not find config file.\n",
+                            PROJECT);
+                    return 1;
+                }
+            }
+            else {
+                fprintf (stderr, "%s: Environment variable HOME must point to "
+                        "the user\'s home directory.\n", PROJECT);
+                return 1;
+            }
+        }
     }
 
     return 0;
@@ -176,7 +332,7 @@ int main (int argc, char *argv[])
 {
     extern int yyparse();
     int rc;                              /* general return code */
-    design_t *tmp;
+    design_t *tmp = (design_t *) rcsid;  /* make rcsid stay */
 
     rc = process_commandline (argc, argv);
     if (rc == 42) exit (EXIT_SUCCESS);