upas/fs: port date parsing to libc apis

There was a lot of code in upas/fs to deal with dates.
Now there isn't.

sys/src/cmd/upas/common/common.h

@@ -52,9 +52,6 @@ char*	ffoldername(char*, char*, char*);
 void	mailfmtinstall(void);	/* 'U' = 2047fmt */
 #pragma varargck	type	"U"	char*
 
-/* totm.c */
-int	fromtotm(char*, Tm*);
-
 /* a pipe between parent and child*/
 typedef struct{
 	Biobuf	bb;

sys/src/cmd/upas/common/folder.c

@@ -1,5 +1,7 @@
 #include "common.h"
 
+#define Ctimefmt "WW MMM _D hh:mm:ss ZZZ YYYY"
+
 enum{
 	Mbox	= 1,
 	Mdir,
@@ -185,7 +187,7 @@ int
 appendfolder(Biobuf *b, char *addr, int fd)
 {
 	char *s;
-	int r;
+	int r, n;
 	Biobuf bin;
 	Folder *f;
 	Tm tm;
@@ -194,9 +196,10 @@ appendfolder(Biobuf *b, char *addr, int fd)
 	Bseek(f->out, 0, 2);
 	Binit(&bin, fd, OREAD);
 	s = Brdstr(&bin, '\n', 0);
-	if(!s || strncmp(s, "From ", 5))
+	n = strlen(s);
+	if(!s || strncmp(s, "From ", 5) != 0)
 		Bprint(f->out, "From %s %.28s\n", addr, ctime(f->t));
-	else if(fromtotm(s, &tm) >= 0)
+	else if(n > 5 && tmparse(&tm, Ctimefmt, s + 5, nil, nil) != nil)
 		f->t = tm2sec(&tm);
 	if(s)
 		Bwrite(f->out, s, strlen(s));

sys/src/cmd/upas/common/mkfile

@@ -10,7 +10,6 @@ OFILES=\
 	fmt.$O\
 	libsys.$O\
 	process.$O\
-	totm.$O\
 
 HFILES=common.h\
 	sys.h\

sys/src/cmd/upas/common/totm.c

@@ -1,36 +0,0 @@
-#include <common.h>
-
-static char mtab[] = "JanFebMarAprMayJunJulAugSepOctNovDec";
-
-int
-ctimetotm(char *s, Tm *tm)
-{
-	char buf[32];
-
-	if(strlen(s) < 28)
-		return -1;
-	snprint(buf, sizeof buf, "%s", s);
-	memset(tm, 0, sizeof *tm);
-	buf[7] = 0;
-	tm->mon = (strstr(mtab, buf+4) - mtab)/3;
-	tm->mday = atoi(buf+8);
-	tm->hour = atoi(buf+11);
-	tm->min = atoi(buf+14);
-	tm->sec = atoi(buf+17);
-	tm->zone[0] = buf[20];
-	tm->zone[1] = buf[21];
-	tm->zone[2] = buf[22];
-	tm->year = atoi(buf+24) - 1900;
-	return 0;
-}
-
-int
-fromtotm(char *s, Tm *tm)
-{
-	char buf[256], *f[3];
-
-	snprint(buf, sizeof buf, "%s", s);
-	if(getfields(buf, f, nelem(f), 0, " ") != 3)
-		return -1;
-	return ctimetotm(f[2], tm);
-}

sys/src/cmd/upas/fs/imap.c

@@ -268,13 +268,10 @@ long
 internaltounix(char *s)
 {
 	Tm tm;
-	if(strlen(s) < 20 || s[2] != '-' || s[6] != '-')
+
+	if(tmparse(&tm, "?DD-?MM-YYYY hh:mm:ss ?Z", s, nil, nil) == nil)
 		return -1;
-	s[2] = ' ';
-	s[6] = ' ';
-	if(strtotm(s, &tm) == -1)
-		return -1;
-	return tm2sec(&tm);
+	return tmnorm(&tm);
 }
 	
 static char*
@@ -981,7 +978,7 @@ again:
 		}
 		if(c < 0){
 			/* new message */
-			idprint(imap, "new: %U (%U)\n", f[i].uid, m? m->imapuid: 0);
+			idprint(imap, "new: %U (%U)\n", f[i].uid, m ? m->imapuid: 0);
 			if(f[i].sizes == 0 || f[i].sizes > Maxmsg){
 				idprint(imap, "skipping bad size: %lud\n", f[i].sizes);
 				i++;

sys/src/cmd/upas/fs/strtotm.c

@@ -1,98 +1,27 @@
 #include <u.h>
 #include <libc.h>
 
-static char*
-skiptext(char *q)
-{
-	while(*q != '\0' && *q != ' ' && *q != '\t' && *q != '\r' && *q != '\n')
-		q++;
-	return q;
-}
-
-static char*
-skipwhite(char *q)
-{
-	while(*q == ' ' || *q == '\t' || *q == '\r' || *q == '\n')
-		q++;
-	return q;
-}
-
-static char* months[] = {
-	"jan", "feb", "mar", "apr",
-	"may", "jun", "jul", "aug",
-	"sep", "oct", "nov", "dec"
-};
-
 int
-strtotm(char *p, Tm *t)
+strtotm(char *s, Tm *t)
 {
-	char *q, *r;
-	int j;
-	Tm tm;
-	int delta;
+	char **f, *fmt[] = {
+		"WW MMM DD hh:mm:ss ?Z YYYY",
+		"?WW ?DD ?MMM ?YYYY hh:mm:ss ?Z",
+		"?WW ?DD ?MMM ?YYYY hh:mm:ss",
+		"?WW, DD-?MM-YY",
+		"?DD ?MMM ?YYYY hh:mm:ss ?Z",
+		"?DD ?MMM ?YYYY hh:mm:ss",
+		"?DD-?MM-YY hh:mm:ss ?Z",
+		"?DD-?MM-YY hh:mm:ss",
+		"?DD-?MM-YY",
+		"?MMM/?DD/?YYYY hh:mm:ss ?Z",
+		"?MMM/?DD/?YYYY hh:mm:ss",
+		"?MMM/?DD/?YYYY",
+		nil,
+	};
 
-	delta = 0;
-	memset(&tm, 0, sizeof(tm));
-	tm.mon = -1;
-	tm.hour = -1;
-	tm.min = -1;
-	tm.year = -1;
-	tm.mday = -1;
-	memcpy(tm.zone, "GMT", 3);
-	for(p = skipwhite(p); *p; p = skipwhite(q)){
-		q = skiptext(p);
-
-		/* look for time in hh:mm[:ss] */
-		if(r = memchr(p, ':', q - p)){
-			tm.hour = strtol(p, 0, 10);
-			tm.min = strtol(r + 1, 0, 10);
-			if(r = memchr(r + 1, ':', q - (r + 1)))
-				tm.sec = strtol(r + 1, 0, 10);
-			else
-				tm.sec = 0;
-			continue;
-		}
-
-		/* look for month */
-		for(j = 0; j < 12; j++)
-			if(cistrncmp(p, months[j], 3) == 0){
-				tm.mon = j;
-				break;
-			}
-		if(j != 12)
-			continue;
-
-		/* look for time zone [A-Z][A-Z]T */
-		if(q - p == 3)
-		if(p[0] >= 'A' && p[0] <= 'Z')
-		if(p[1] >= 'A' && p[1] <= 'Z')
-		if(p[2] == 'T'){
-			strecpy(tm.zone, tm.zone + 4, p);
-			continue;
-		}
-
-		if(p[0] == '+'||p[0] == '-')
-		if(q - p == 5 && strspn(p + 1, "0123456789") == 4){
-			delta = (((p[1] - '0')*10 + p[2] - '0')*60 + (p[3] - '0')*10 + p[4] - '0')*60;
-			if(p[0] == '-')
-				delta = -delta;
-			continue;
-		}
-		if(strspn(p, "0123456789") == q - p){
-			j = strtol(p, nil, 10);
-			if(j >= 1 && j <= 31)
-				tm.mday = j;
-			if(j >= 1900)
-				tm.year = j - 1900;
-			continue;
-		}
-		//eprint("strtotm: garbage %.*s\n", utfnlen(p, q - p), p);
-	}
-	if(tm.mon < 0 || tm.year < 0
-	|| tm.hour < 0 || tm.min < 0
-	|| tm.mday < 0)
-		return -1;
-
-	*t = *localtime(tm2sec(&tm) - delta);
-	return 0;
+	for(f = fmt; *f; f++)
+		if(tmparse(t, *f, s, nil, nil) != nil)
+			return 0;
+	return -1;
 }