epan/wslua/wslua_nstime.c

   1 /*
   2  * wslua_nstime.c
   3  *
   4  * Wireshark's interface to the Lua Programming Language
   5  *
   6  * (c) 2006, Luis E. Garcia Ontanon <luis@ontanon.org>
   7  * (c) 2008, Balint Reczey <balint.reczey@ericsson.com>
   8  * (c) 2011, Stig Bjorlykke <stig@bjorlykke.org>
   9  * (c) 2014, Hadriel Kaplan <hadrielk@yahoo.com>
  10  *
  11  * Wireshark - Network traffic analyzer
  12  * By Gerald Combs <gerald@wireshark.org>
  13  * Copyright 1998 Gerald Combs
  14  *
  15  * SPDX-License-Identifier: GPL-2.0-or-later
  16  */
  17
  18 #include "config.h"
  19
  20 #include "wslua.h"
  21 #include <wsutil/nstime.h>
  22
  23 /* 1s = 10^9 ns. */
  24 #define NS_PER_S 1000000000
  25
  26 /* WSLUA_CONTINUE_MODULE Pinfo */
  27
  28
  29 WSLUA_CLASS_DEFINE(NSTime,FAIL_ON_NULL("NSTime"));
  30 /* NSTime represents a nstime_t.  This is an object with seconds and nanoseconds. */
  31
  32 WSLUA_CONSTRUCTOR NSTime_new(lua_State *L) {
  33     /* Creates a new NSTime object. */
  34 #define WSLUA_OPTARG_NSTime_new_SECONDS 1 /* Seconds. */
  35 #define WSLUA_OPTARG_NSTime_new_NSECONDS 2 /* Nano seconds. */
  36     lua_Integer secs = luaL_optinteger(L,WSLUA_OPTARG_NSTime_new_SECONDS,0);
  37     lua_Integer nsecs = luaL_optinteger(L,WSLUA_OPTARG_NSTime_new_NSECONDS,0);
  38
  39     NSTime nstime = g_new(nstime_t, 1);
  40     if (!nstime) return 0;
  41     nstime->secs = (time_t) secs;
  42     nstime->nsecs = (int) nsecs;
  43
  44     pushNSTime(L,nstime);
  45
  46     WSLUA_RETURN(1); /* The new NSTime object. */
  47 }
  48
  49 WSLUA_METAMETHOD NSTime__call(lua_State* L) { /* Creates a NSTime object. */
  50 #define WSLUA_OPTARG_NSTime__call_SECONDS 1 /* Seconds. */
  51 #define WSLUA_OPTARG_NSTime__call_NSECONDS 2 /* Nanoseconds. */
  52     lua_remove(L,1); /* remove the table */
  53     WSLUA_RETURN(NSTime_new(L)); /* The new NSTime object. */
  54 }
  55
  56 WSLUA_METHOD NSTime_tonumber(lua_State* L) {
  57         /* Returns a Lua number of the `NSTime` representing seconds from epoch. */
  58         NSTime nstime = checkNSTime(L,1);
  59         lua_pushnumber(L, (lua_Number)nstime_to_sec(nstime));
  60         WSLUA_RETURN(1); /* The Lua number. */
  61 }
  62
  63 WSLUA_METAMETHOD NSTime__tostring(lua_State* L) {
  64     NSTime nstime = checkNSTime(L,1);
  65     char *str;
  66     long secs = (long)nstime->secs;
  67     int nsecs = nstime->nsecs;
  68     bool negative_zero = false;
  69
  70     /* Time is defined as sec + nsec/10^9, both parts can be negative.
  71      * Translate this into the more familiar sec.nsec notation instead. */
  72     if (secs > 0 && nsecs < 0) {
  73         /* sign mismatch: (2, -3ns) -> 1.7 */
  74         nsecs += NS_PER_S;
  75         secs--;
  76     } else if (secs < 0 && nsecs > 0) {
  77         /* sign mismatch: (-2, 3ns) -> -1.7 */
  78         nsecs = NS_PER_S - nsecs;
  79         secs--;
  80     } else if (nsecs < 0) {
  81         /* Drop sign, the integer part already has it: (-2, -3ns) -> -2.3 */
  82         nsecs = -nsecs;
  83         /* In case the integer part is zero, it does not has a sign, so remember
  84          * that it must be explicitly added. */
  85         negative_zero = secs == 0;
  86     }
  87
  88     if (negative_zero) {
  89         str = wmem_strdup_printf(NULL, "-0.%09d", nsecs);
  90     } else {
  91         str = wmem_strdup_printf(NULL, "%ld.%09d", secs, nsecs);
  92     }
  93     lua_pushstring(L, str);
  94     wmem_free(NULL, str);
  95
  96     WSLUA_RETURN(1); /* The string representing the nstime. */
  97 }
  98 WSLUA_METAMETHOD NSTime__add(lua_State* L) { /* Calculates the sum of two NSTimes. */
  99     NSTime time1 = checkNSTime(L,1);
 100     NSTime time2 = checkNSTime(L,2);
 101     NSTime time3 = (NSTime)g_malloc (sizeof (nstime_t));
 102
 103     nstime_sum (time3, time1, time2);
 104     pushNSTime (L, time3);
 105
 106     return 1;
 107 }
 108
 109 WSLUA_METAMETHOD NSTime__sub(lua_State* L) { /* Calculates the diff of two NSTimes. */
 110     NSTime time1 = checkNSTime(L,1);
 111     NSTime time2 = checkNSTime(L,2);
 112     NSTime time3 = (NSTime)g_malloc (sizeof (nstime_t));
 113
 114     nstime_delta (time3, time1, time2);
 115     pushNSTime (L, time3);
 116
 117     return 1;
 118 }
 119
 120 WSLUA_METAMETHOD NSTime__unm(lua_State* L) { /* Calculates the negative NSTime. */
 121     NSTime time1 = checkNSTime(L,1);
 122     NSTime time2 = (NSTime)g_malloc (sizeof (nstime_t));
 123
 124     nstime_set_zero (time2);
 125     nstime_subtract (time2, time1);
 126     pushNSTime (L, time2);
 127
 128     return 1;
 129 }
 130
 131 WSLUA_METAMETHOD NSTime__eq(lua_State* L) { /* Compares two NSTimes. */
 132     NSTime time1 = checkNSTime(L,1);
 133     NSTime time2 = checkNSTime(L,2);
 134     bool result = false;
 135
 136     if (nstime_cmp(time1, time2) == 0)
 137         result = true;
 138
 139     lua_pushboolean(L,result);
 140
 141     return 1;
 142 }
 143
 144 WSLUA_METAMETHOD NSTime__le(lua_State* L) { /* Compares two NSTimes. */
 145     NSTime time1 = checkNSTime(L,1);
 146     NSTime time2 = checkNSTime(L,2);
 147     bool result = false;
 148
 149     if (nstime_cmp(time1, time2) <= 0)
 150         result = true;
 151
 152     lua_pushboolean(L,result);
 153
 154     return 1;
 155 }
 156
 157 WSLUA_METAMETHOD NSTime__lt(lua_State* L) { /* Compares two NSTimes. */
 158     NSTime time1 = checkNSTime(L,1);
 159     NSTime time2 = checkNSTime(L,2);
 160     bool result = false;
 161
 162     if (nstime_cmp(time1, time2) < 0)
 163         result = true;
 164
 165     lua_pushboolean(L,result);
 166
 167     return 1;
 168 }
 169
 170
 171 /* WSLUA_ATTRIBUTE NSTime_secs RW The NSTime seconds. */
 172 WSLUA_ATTRIBUTE_INTEGER_GETTER(NSTime,secs);
 173 WSLUA_ATTRIBUTE_INTEGER_SETTER(NSTime,secs,time_t);
 174
 175 /* WSLUA_ATTRIBUTE NSTime_nsecs RW The NSTime nano seconds. */
 176 WSLUA_ATTRIBUTE_INTEGER_GETTER(NSTime,nsecs);
 177 WSLUA_ATTRIBUTE_INTEGER_SETTER(NSTime,nsecs,int);
 178
 179 /* Gets registered as metamethod automatically by WSLUA_REGISTER_CLASS/META */
 180 static int NSTime__gc(lua_State* L) {
 181     NSTime nstime = toNSTime(L,1);
 182
 183     if (!nstime) return 0;
 184
 185     g_free (nstime);
 186     return 0;
 187 }
 188
 189 /* This table is ultimately registered as a sub-table of the class' metatable,
 190  * and if __index/__newindex is invoked then it calls the appropriate function
 191  * from this table for getting/setting the members.
 192  */
 193 WSLUA_ATTRIBUTES NSTime_attributes[] = {
 194     WSLUA_ATTRIBUTE_RWREG(NSTime,secs),
 195     WSLUA_ATTRIBUTE_RWREG(NSTime,nsecs),
 196     { NULL, NULL, NULL }
 197 };
 198
 199 WSLUA_METHODS NSTime_methods[] = {
 200     WSLUA_CLASS_FNREG(NSTime,new),
 201     WSLUA_CLASS_FNREG(NSTime,tonumber),
 202     { NULL, NULL }
 203 };
 204
 205 WSLUA_META NSTime_meta[] = {
 206     WSLUA_CLASS_MTREG(NSTime,tostring),
 207     WSLUA_CLASS_MTREG(NSTime,add),
 208     WSLUA_CLASS_MTREG(NSTime,sub),
 209     WSLUA_CLASS_MTREG(NSTime,unm),
 210     WSLUA_CLASS_MTREG(NSTime,eq),
 211     WSLUA_CLASS_MTREG(NSTime,le),
 212     WSLUA_CLASS_MTREG(NSTime,lt),
 213     WSLUA_CLASS_MTREG(NSTime,call),
 214    { NULL, NULL }
 215 };
 216
 217 int NSTime_register(lua_State* L) {
 218     WSLUA_REGISTER_CLASS_WITH_ATTRS(NSTime);
 219     return 0;
 220 }
 221
 222
 223 /*
 224  * Editor modelines  -  https://www.wireshark.org/tools/modelines.html
 225  *
 226  * Local variables:
 227  * c-basic-offset: 4
 228  * tab-width: 8
 229  * indent-tabs-mode: nil
 230  * End:
 231  *
 232  * vi: set shiftwidth=4 tabstop=8 expandtab:
 233  * :indentSize=4:tabSize=8:noTabs=true:
 234  */