X-Git-Url: https://diplodocus.org/git/nmh/blobdiff_plain/84b0fcf3611555f616abf2dcc80ec30b18f16e29..4af72ec87eefd3d87da44411557c95c88c2bf3a1:/sbr/fmt_scan.c

diff --git a/sbr/fmt_scan.c b/sbr/fmt_scan.c
index 1d8dd29c..cb29b72c 100644
--- a/sbr/fmt_scan.c
+++ b/sbr/fmt_scan.c
@@ -9,6 +9,11 @@
  */
 
 #include "h/mh.h"
+#include "fmt_addr.h"
+#include "dtime.h"
+#include "strindex.h"
+#include "fmt_rfc2047.h"
+#include "uprf.h"
 #include "context_find.h"
 #include "error.h"
 #include "h/addrsbr.h"
@@ -65,56 +70,66 @@ match (char *str, char *sub)
     return 1;
 }
 
-/*
- * copy a number to the destination subject to a maximum width
- */
+/* cpnumber formats num as a signed decimal,
+ * appending it to dest if the result doesn't exceed max.
+ * The absolute value of width is the minimum width to produce.
+ * A smaller string is padded;
+ * on the left if width is positive, else the right.
+ * Left-padding uses fill.  It is either ' ' or '0'.
+ * Right-padding is always with space. */
 void
-cpnumber(charstring_t dest, int num, int wid, char fill, size_t max)
+cpnumber(charstring_t dest, int num, int width, char fill, size_t max)
 {
-    /* Maybe we should handle left padding at some point? */
-    if (wid == 0)
-	return;
-    if (wid < 0)
-        wid = -wid; /* OK because wid originally a short. */
-    if ((size_t)wid < (num >= 0 ? max : max-1)) {
-	/* Build up the string representation of num in reverse. */
-	charstring_t rev = charstring_create (0);
-	int i = num >= 0 ? num : -num;
-
-	do {
-	    charstring_push_back (rev, i % 10  +  '0');
-	    i /= 10;
-	} while (--wid > 0  &&  i > 0);
-	if (i > 0) {
-	    /* Overflowed the field (wid). */
-	    charstring_push_back (rev, '?');
-	} else if (num < 0  &&  wid > 0) {
-	    /* Shouldn't need the wid > 0 check, that's why the condition
-	       at the top checks wid < max-1 when num < 0. */
-	    --wid;
-	    if (fill == ' ') {
-		charstring_push_back (rev, '-');
-	    }
-	}
-	while (wid-- > 0  &&  fill != 0) {
-	    charstring_push_back (rev, fill);
-	}
-	if (num < 0  &&  fill == '0') {
-	    charstring_push_back (rev, '-');
-	}
+    if (width == 0 || width == INT_MIN) {
+        return;
+    }
 
-	{
-	    /* Output the string in reverse. */
-	    size_t b = charstring_bytes (rev);
-	    const char *cp = b  ?  &charstring_buffer (rev)[b]  :  NULL;
+    bool padright = width < 0;
+    if (padright) {
+        width = -width; /* Can't overflow after above check. */
+    }
+    size_t w = width;
+    if (w > max) {
+        return; /* The padded result can't fit. */
+    }
+    if (num < 0 && w == 1) {
+        return; /* No room for `-' and a digit or `?'. */
+    }
 
-	    for (; b > 0; --b) {
-		charstring_push_back (dest, *--cp);
-	    }
-	}
+    char *s = m_str(num);
+    size_t len = strlen(s);
+    if (len == w) {
+        charstring_append_cstring(dest, s);
+        return;
+    }
+
+    bool neg = *s == '-';
+    if (len < w) {
+        if (padright) {
+            charstring_append_cstring(dest, s);
+            while (len++ < w) {
+                charstring_push_back(dest, ' ');
+            }
+            return;
+        }
+
+        if (neg && fill == '0') {
+            charstring_push_back(dest, *s++);
+        }
+        while (len++ < w) {
+            charstring_push_back(dest, fill);
+        }
+        charstring_append_cstring(dest, s);
+        return;
+    }
 
-	charstring_free (rev);
+    /* Transform 1234567 -> 1234?67 and -1234567 -> 1234-?7. */
+    char *news = s + len - w;
+    if (neg) {
+        *news = '-';
     }
+    news[neg] = '?';
+    charstring_append_cstring(dest, news);
 }
 
 /*
@@ -398,7 +413,10 @@ fmt_scan (struct format *format, charstring_t scanlp, int width, int *dat,
 	  struct fmt_callbacks *callbacks)
 {
     char *sp;
-    char *savestr, *str;
+    /* If str points to part of buffer[] or buffer2[] then it must only
+     * ever point at their first element as otherwise undefined
+     * behaviour from overlapping strncpy(3)s can result. */
+    char *str, *savestr;
     char buffer[NMH_BUFSIZ], buffer2[NMH_BUFSIZ];
     int i, c;
     bool rjust;
@@ -742,6 +760,7 @@ fmt_scan (struct format *format, charstring_t scanlp, int width, int *dat,
 			    *xp-- = '\0';
 		    if (rjust && i > 0 && (int) strlen(str) > i)
 			str += strlen(str) - i;
+                    str = memmove(buffer, str, strlen(str) + 1);
 	    }
 	    break;
 
@@ -776,15 +795,18 @@ fmt_scan (struct format *format, charstring_t scanlp, int width, int *dat,
 	    value *= fmt->f_value;
 	    break;
 	case FT_LV_DIVIDE_L:
-	    if (fmt->f_value)
-		value /= fmt->f_value;
-	    else
+            if (fmt->f_value == 0 || (fmt->f_value == -1 && value == INT_MIN)) {
+                // FIXME: Tell the user, and probably stop.
 		value = 0;
+            } else {
+                value /= fmt->f_value;
+            }
 	    break;
 	case FT_LV_MODULO_L:
 	    if (fmt->f_value)
 		value %= fmt->f_value;
 	    else
+                // FIXME: Tell the user, and probably stop.
 		value = 0;
 	    break;
 	case FT_SAVESTR:
@@ -931,6 +953,7 @@ fmt_scan (struct format *format, charstring_t scanlp, int width, int *dat,
 	            	    else
 	            		break;
 	            }
+                    str = memmove(buffer, str, strlen(str) + 1);
 	        } else if (!(str = get_x400_friendly (mn->m_mbox,
 				buffer, sizeof(buffer)))) {
 	unfriendly: