1 /* Implementation of the CTIME and FDATE g77 intrinsics.
2    Copyright (C) 2005-2019 Free Software Foundation, Inc.
3    Contributed by François-Xavier Coudert <coudert@clipper.ens.fr>
4 
5 This file is part of the GNU Fortran runtime library (libgfortran).
6 
7 Libgfortran is free software; you can redistribute it and/or
8 modify it under the terms of the GNU General Public
9 License as published by the Free Software Foundation; either
10 version 3 of the License, or (at your option) any later version.
11 
12 Libgfortran is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 GNU General Public License for more details.
16 
17 Under Section 7 of GPL version 3, you are granted additional
18 permissions described in the GCC Runtime Library Exception, version
19 3.1, as published by the Free Software Foundation.
20 
21 You should have received a copy of the GNU General Public License and
22 a copy of the GCC Runtime Library Exception along with this program;
23 see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
24 <http://www.gnu.org/licenses/>.  */
25 
26 #include "libgfortran.h"
27 
28 #include "time_1.h"
29 
30 #include <string.h>
31 
32 
33 /* Maximum space a ctime-like string might need. A "normal" ctime
34    string is 26 bytes, and in our case 24 bytes as we don't include
35    the trailing newline and null. However, the longest possible year
36    number is -2,147,481,748 (1900 - 2,147,483,648, since tm_year is a
37    32-bit signed integer) so an extra 7 bytes are needed. */
38 #define CTIME_BUFSZ 31
39 
40 
41 /* Thread-safe ctime-like function that fills a Fortran
42    string. ctime_r is a portability headache and marked as obsolescent
43    in POSIX 2008, which recommends strftime in its place. However,
44    strftime(..., "%c",...)  doesn't produce ctime-like output on
45    MinGW, so do it manually with snprintf.  */
46 
47 static int
gf_ctime(char * s,size_t max,const time_t timev)48 gf_ctime (char *s, size_t max, const time_t timev)
49 {
50   struct tm ltm;
51   int failed;
52   char buf[CTIME_BUFSZ + 1];
53   /* Some targets provide a localtime_r based on a draft of the POSIX
54      standard where the return type is int rather than the
55      standardized struct tm*.  */
56   __builtin_choose_expr (__builtin_classify_type (localtime_r (&timev, &ltm))
57 			 == 5,
58 			 failed = localtime_r (&timev, &ltm) == NULL,
59 			 failed = localtime_r (&timev, &ltm) != 0);
60   if (failed)
61     goto blank;
62   int n = snprintf (buf, sizeof (buf),
63 		    "%3.3s %3.3s%3d %.2d:%.2d:%.2d %d",
64 		    "SunMonTueWedThuFriSat" + ltm.tm_wday * 3,
65 		    "JanFebMarAprMayJunJulAugSepOctNovDec" + ltm.tm_mon * 3,
66 		    ltm.tm_mday, ltm.tm_hour, ltm.tm_min, ltm.tm_sec,
67 		    1900 + ltm.tm_year);
68   if (n < 0)
69     goto blank;
70   if ((size_t) n <= max)
71     {
72       cf_strcpy (s, max, buf);
73       return n;
74     }
75  blank:
76   memset (s, ' ', max);
77   return 0;
78 }
79 
80 
81 extern void fdate (char **, gfc_charlen_type *);
82 export_proto(fdate);
83 
84 void
fdate(char ** date,gfc_charlen_type * date_len)85 fdate (char ** date, gfc_charlen_type * date_len)
86 {
87   time_t now = time(NULL);
88   *date = xmalloc (CTIME_BUFSZ);
89   *date_len = gf_ctime (*date, CTIME_BUFSZ, now);
90 }
91 
92 
93 extern void fdate_sub (char *, gfc_charlen_type);
94 export_proto(fdate_sub);
95 
96 void
fdate_sub(char * date,gfc_charlen_type date_len)97 fdate_sub (char * date, gfc_charlen_type date_len)
98 {
99   time_t now = time(NULL);
100   gf_ctime (date, date_len, now);
101 }
102 
103 
104 
105 extern void PREFIX(ctime) (char **, gfc_charlen_type *, GFC_INTEGER_8);
106 export_proto_np(PREFIX(ctime));
107 
108 void
PREFIX(ctime)109 PREFIX(ctime) (char ** date, gfc_charlen_type * date_len, GFC_INTEGER_8 t)
110 {
111   time_t now = t;
112   *date = xmalloc (CTIME_BUFSZ);
113   *date_len = gf_ctime (*date, CTIME_BUFSZ, now);
114 }
115 
116 
117 extern void ctime_sub (GFC_INTEGER_8 *, char *, gfc_charlen_type);
118 export_proto(ctime_sub);
119 
120 void
ctime_sub(GFC_INTEGER_8 * t,char * date,gfc_charlen_type date_len)121 ctime_sub (GFC_INTEGER_8 * t, char * date, gfc_charlen_type date_len)
122 {
123   time_t now = *t;
124   gf_ctime (date, date_len, now);
125 }
126