Lua update strftime.c from dietlibc source

Adds %F -- %Y-%m-%d
Fixes possible buffer overflow when writing final \0
Frees a bit of code on NON-RTC targets

Change-Id: I1c2600a68ee88c6c99f411ae6646861578683f90

1 files changed, 38 insertions, 36 deletions

diff --git a/apps/plugins/lua/strftime.c b/apps/plugins/lua/strftime.c
index 681d4be1cf..c6152bf492 100644
--- a/apps/plugins/lua/strftime.c
+++ b/apps/plugins/lua/strftime.c
@@ -45,16 +45,17 @@ size_t  strftime ( char* dst, size_t max, const char* format, const struct tm* t
         else
 again:
         switch (*format) {
-//          case '%': *p++ = '%';                break;         // reduce size of jump table
-        case 'n': *p++ = '\n';               break;
-        case 't': *p++ = '\t';               break;
+//          case '%': *p++ = '%';                  break;            // reduce size of jump table
+        case 'n': *p++ = '\n';                 break;
+        case 't': *p++ = '\t';                 break;
         case 'O': case 'E': ++format; goto again;
-        case 'c': src = "%b %a %d %k:%M:%S %Z %Y";           goto _strf;
-        case 'r': src = "%I:%M:%S %p";                       goto _strf;
-        case 'R': src = "%H:%M";                 goto _strf;
-        case 'x': src = "%b %a %d";              goto _strf;
-        case 'X': src = "%k:%M:%S";              goto _strf;
-        case 'D': src = "%m/%d/%y";              goto _strf;
+        case 'c': src = "%b %a %d %k:%M:%S %Z %Y";            goto _strf;
+        case 'r': src = "%I:%M:%S %p";                        goto _strf;
+        case 'R': src = "%H:%M";                  goto _strf;
+        case 'x': src = "%b %a %d";               goto _strf;
+        case 'X': src = "%k:%M:%S";               goto _strf;
+        case 'D': src = "%m/%d/%y";               goto _strf;
+        case 'F': src = "%Y-%m-%d";               goto _strf;
         case 'T': src = "%H:%M:%S";
            _strf: p  += strftime (p, (size_t)(dst+max-p), src, tm);      break;
         case 'a': src = sweekdays [tm->tm_wday];         goto _str;
@@ -64,37 +65,35 @@ again:
         case 'B': src = months    [tm->tm_mon];          goto _str;
         case 'p': src = ampm [tm->tm_hour > 12 ? 3 : 2]; goto _str;
         case 'P': src = ampm [tm->tm_hour > 12 ? 1 : 0]; goto _str;
-        case 'C': no  = tm->tm_year/100 + 19;        goto _no;
-        case 'd': no  = tm->tm_mday;                 goto _no;
-        case 'e': no  = tm->tm_mday;                 goto _nos;
-        case 'H': no  = tm->tm_hour;                 goto _no;
-        case 'I': no  = tm->tm_hour % 12;            goto _no;
-        case 'j': no  = tm->tm_yday;                 goto _no;
-        case 'k': no  = tm->tm_hour;                 goto _nos;
-        case 'l': no  = tm->tm_hour % 12;            goto _nos;
-        case 'm': no  = tm->tm_mon + 1;                  goto _no;
-        case 'M': no  = tm->tm_min;                  goto _no;
-        case 'S': no  = tm->tm_sec;                  goto _no;
-        case 'u': no  = tm->tm_wday ? tm->tm_wday : 7;   goto _no;
-        case 'w': no  = tm->tm_wday;                     goto _no;
+        case 'C': no  = tm->tm_year/100 + 19;         goto _no;
+        case 'd': no  = tm->tm_mday;                  goto _no;
+        case 'e': no  = tm->tm_mday;                  goto _nos;
+        case 'H': no  = tm->tm_hour;                  goto _no;
+        case 'I': no  = tm->tm_hour % 12;             goto _no;
+        case 'j': no  = tm->tm_yday;                  goto _no;
+        case 'k': no  = tm->tm_hour;                  goto _nos;
+        case 'l': no  = tm->tm_hour % 12;             goto _nos;
+        case 'm': no  = tm->tm_mon + 1;               goto _no;
+        case 'M': no  = tm->tm_min;                   goto _no;
+        case 'S': no  = tm->tm_sec;                   goto _no;
+        case 'u': no  = tm->tm_wday ? tm->tm_wday : 7;       goto _no;
+        case 'w': no  = tm->tm_wday;                         goto _no;
         case 'U': no  = (tm->tm_yday - tm->tm_wday + 7) / 7; goto _no;
         case 'W': no  = (tm->tm_yday - (tm->tm_wday - 1 + 7) % 7 + 7) / 7; goto _no;
         case 's': {
-            time_t t =
 #if CONFIG_RTC
-                rb->mktime((struct tm*)tm)
-#else
-                0
-#endif
-            ;
-            char buf[101];
+            time_t t = rb->mktime((struct tm*)tm);
+            char sbuf[101];
             char* c;
-            buf[100]=0;
-            for (c=buf+99; c>buf; --c) {
+            sbuf[100]=0;
+            for (c=sbuf+99; c>sbuf; --c) {
               *c=(t%10)+'0';
               t/=10;
               if (!t) break;
             }
+#else
+            char* c = "0";
+#endif
             src=c;
             goto _str;
               }
@@ -109,15 +108,15 @@ again:
               i2a ( buf+2, (unsigned int)(tm->tm_year % 100) );
               src = buf;
               goto _str;
-        case 'y': no  = tm->tm_year % 100;           goto _no;
-         _no: i2a ( buf, no );               /* append number 'no' */
+        case 'y': no  = tm->tm_year % 100;              goto _no;
+         _no: i2a ( buf, no );                 /* append number 'no' */
               src = buf;
               goto _str;
-        _nos: i2a ( buf, no );               /* the same, but '0'->' ' */
+        _nos: i2a ( buf, no );                 /* the same, but '0'->' ' */
               if (buf[0] == '0')
               buf[0] = ' ';
               src = buf;
-        _str: while (*src  &&  p < dst+max)      /* append string */
+        _str: while (*src  &&  p < dst+max)         /* append string */
               *p++ = *src++;
               break;
         };
@@ -129,7 +128,10 @@ again:
         break;
     }
 
-    *p = '\0';
+    if ((size_t)(p-dst)>=max) {
+      if (max) p[-1]=0;
+    } else
+      *p = '\0';
     return p - dst;
 }