birthday/date implementation

Makefile

@@ -142,6 +142,14 @@ UPROGS=\
 	$U/_logstress\
 	$U/_forphan\
 	$U/_dorphan\
+	$U/_date\
+	$U/_birthday\
+
+$U/_birthday: $U/birthday.o $U/time.o $(ULIB)
+	$(LD) $(LDFLAGS) -T $U/user.ld -o $U/_birthday $U/birthday.o $U/time.o $(ULIB)
+
+$U/_date: $U/date.o $U/time.o $(ULIB)
+	$(LD) $(LDFLAGS) -T $U/user.ld -o $U/_date $U/date.o $U/time.o $(ULIB)
 
 fs.img: mkfs/mkfs README.md $(UPROGS)
 	mkfs/mkfs fs.img README.md $(UPROGS)

docs/birthday-date.md

@@ -0,0 +1,31 @@
+---- FogOSv2 Birthday, Date, Time Help Guide ----
+-- Running --
+Run make, make qemu. 
+
+-- Makefile --
+Add 'birthday' and 'date' to UPROGS.
+Build 'birthday' and 'date' with 'time' object.
+
+-- Kernel Activity --
+Clock is a necessary system call.
+
+-- Birthday --
+birthday | birthday with no flags. If the birthday is set, then it will tell the user "happy 
+happy", otherwise it will tell the user not yet!
+birthday '-s' [MM/DD] | birthday with -s flag will set the birthday. Must be in MM/DD format
+where both are integers.
+
+-- Date --
+date | only command for date. This will return the date in format: MMM DD HH:MM:SS PDT YYYY
+Note: MMM is a string. The rest are integers besides PDT.
+
+-- Time --
+time.c and time.h are required for date and time to work. Time is not a usable command.
+
+-- Testing --
+To test, try:
+1. Calling 'birthday' before it is set.
+2. Setting 'birthday' with parameters M/DD.
+3. Setting 'birthday' with an impossible date.
+4. Setting 'birthday' with today's date and calling it. 
+5. Setting 'birthday' with your birthday and calling it. 

kernel/memlayout.h

@@ -57,3 +57,6 @@
 //   TRAPFRAME (p->trapframe, used by the trampoline)
 //   TRAMPOLINE (the same page as in the kernel)
 #define TRAPFRAME (TRAMPOLINE - PGSIZE)
+
+// goldfish real time clock memory adress
+#define GOLD_RTC 0x101000

kernel/syscall.c

@@ -101,6 +101,7 @@ extern uint64 sys_unlink(void);
 extern uint64 sys_link(void);
 extern uint64 sys_mkdir(void);
 extern uint64 sys_close(void);
+extern uint64 sys_clock(void);
 
 // An array mapping syscall numbers from syscall.h
 // to the function that handles the system call.
@@ -126,6 +127,7 @@ static uint64 (*syscalls[])(void) = {
 [SYS_link]    sys_link,
 [SYS_mkdir]   sys_mkdir,
 [SYS_close]   sys_close,
+[SYS_clock]   sys_clock,
 };
 
 void

kernel/syscall.h

@@ -20,3 +20,4 @@
 #define SYS_link   19
 #define SYS_mkdir  20
 #define SYS_close  21
+#define SYS_clock 22

kernel/sysproc.c

@@ -105,3 +105,12 @@ sys_uptime(void)
   release(&tickslock);
   return xticks;
 }
+
+uint64
+sys_clock(void)
+{
+    volatile uint32 *clock = (uint32 *) GOLD_RTC;
+    uint32 top = clock[0];
+    uint32 btm = clock[1];
+    return ((uint64) btm << 32) | top;
+}

kernel/vm.c

@@ -35,6 +35,9 @@ kvmmake(void)
   // PLIC
   kvmmap(kpgtbl, PLIC, PLIC, 0x4000000, PTE_R | PTE_W);
 
+  // map golfish real time clock
+  kvmmap(kpgtbl, GOLD_RTC, GOLD_RTC, PGSIZE, PTE_R);
+
   // map kernel text executable and read-only.
   kvmmap(kpgtbl, KERNBASE, KERNBASE, (uint64)etext-KERNBASE, PTE_R | PTE_X);
 

user/birthday.c

@@ -0,0 +1,133 @@
+#include "kernel/types.h"
+#include "kernel/stat.h"
+#include "user/user.h"
+#include "kernel/fcntl.h"
+#include "kernel/param.h"
+#include "time.h"
+
+static const int days_per_month[] = {
+    31, 28, 31, 30, 31, 30, 
+    31, 31, 30, 31, 30, 31
+};
+
+int validate_birthdate(char buf[]) {
+    if (strlen(buf) != 5) { // not MM/DD
+        return 0;
+    }
+
+    int i = 0, month = 0, day = 0;
+    while (buf[i] != '\0') {
+        if ((buf[i] == '/') ||(buf[i] >= '1' && buf[i] <= '9')) {
+            if (i < 2) {
+                month = month * 10 + (buf[i] - '0'); 
+            } else if (i > 2) {
+                day = day * 10 + (buf[i] - '0'); 
+            } 
+        }
+        ++i;
+    }
+
+    if ((month < 1) || (month > 12) || (day > days_per_month[month-1] && month != 2 && day != 29) || (day < 1)) {
+        return 0;        
+    }
+
+    return 1;
+}
+
+void print_usage() {
+    printf("Usage:\n");
+    printf("birthday            # if set, check if it's your birthday\n");
+    printf("birthday -s MM/DD   # (re)set birthday\n");
+}
+
+int main(int argc, char *argv[]) {
+    /* 
+        birthday command in use
+        $birthday - No arguments, if birthday is set, return predefined
+        statements. else, ask to set birthday.
+        $birthday -s  [MM/DD] - Set birthday
+    */
+
+    struct stat st; // check if birthday file exists
+    int fd; // for open, write, close
+    char buf[MAXPATH]; // for write
+
+    int month = 0, day = 0,  i = 0; // for comparisons
+
+    int exists = (stat("birthday.txt", &st) == 0);
+
+    // proper length and checking flag
+    if ((argc == 3) && (argv[1][0] == '-' && argv[1][1] == 's')) {
+        if (!validate_birthdate(argv[2])) {
+            print_usage();
+            return -1;
+        }
+
+        fd = open("birthday.txt", O_CREATE | O_RDWR | O_TRUNC);
+            if (fd < 0) { // error
+            return -1;
+        }
+        write(fd, argv[2], strlen(argv[2]));
+        close(fd);
+        return 0; 
+    } 
+    if (argc == 1 && exists) {
+        fd = open("birthday.txt", O_RDWR);
+        if (fd < 0) { // error
+            return -1;
+        }
+        int n = read(fd, buf, sizeof(buf) - 1);
+
+        if(n < 0){
+            close(fd);
+            return -1;
+        }
+        buf[n] = '\0';
+
+        while (buf[i] != '\0') {
+            if (i < 2) {
+                month = month * 10 + (buf[i] - '0'); 
+            } else if (i > 2) {
+                day = day * 10 + (buf[i] - '0'); 
+            }
+            ++i;
+        }
+
+        uint64 c = clock() / 1000000000ULL;
+        uint64 local_date = c - (7 * 3600);
+        datetime date = to_datetime(local_date);
+
+        if (date.month == month && date.day == day) {
+            printf(
+            "              (        (\n"
+            "             ( )      ( )          (\n"
+            "      (       Y        Y          ( )\n"
+            "     ( )     | |      | |          Y\n"
+            "      Y      | |      | |         | |\n"
+            "     | |     | |.-----| |---.___  | |\n"
+            "     | |  .--| |,~~~~~| |~~~,,,,'-| |\n"
+            "     | |-,,~~'-'___   '-'       ~~| |._\n"
+            "    .| |~       // ___            '-',,'.\n"
+            "   /,'-'     <_// // _  __             ~,\\\n"
+            "  / ;     ,-,     \\_> <<_______________;_)\n"
+            "  | ;    {(_)} _,      . |================|\n"
+            "  | '-._ ~~,,,           | ,,             |\n"
+            "  |     '-.__ ~~~~~~~~~~~|________________|   \n"
+            "  |\\         `'----------|\n"
+            "  | '=._                 |\n"
+            "  :     '=.__            |\n"
+            "   \\         `'==========|\n"
+            "snd '-._                 |\n"
+            "        '-.__            |\n"
+            "             ``''--------|\n"
+            );
+            printf("Happy Birthday!\n");
+        } else {
+            printf("Uh oh. It's not your birthday yet :(\n");
+        }
+        return 0;    
+    }
+
+    print_usage(); // otherwise, fail. 
+    return -1;
+}

user/date.c

@@ -0,0 +1,21 @@
+#include "kernel/types.h"
+#include "kernel/stat.h"
+#include "user/user.h"
+#include "time.h"
+
+static const char* month_name[] = {
+    "Jan", "Feb", "Mar", "Apr", "May", "June",
+    "July", "Aug", "Sep", "Oct", "Nov", "Dec"
+};
+
+int main() {
+    uint64 c = clock() / 1000000000ULL;
+    uint64 local_date = c - (7 * 3600);
+    datetime date = to_datetime(local_date);
+
+    printf("%s %d %d:%d:%d PDT %d\n", 
+    month_name[date.month-1], date.day, 
+    date.hour, date.minute, date.second, 
+    date.year);
+    return 0;
+}

user/time.c

@@ -0,0 +1,61 @@
+#include "kernel/types.h"
+#include "kernel/stat.h"
+#include "user/user.h"
+#include "time.h"
+
+int is_leap(int year) {
+    return (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
+}
+
+static const int days_per_month[] = {
+    31, 28, 31, 30, 31, 30, 
+    31, 31, 30, 31, 30, 31
+};
+
+datetime to_datetime(uint64 timestamp) {
+    datetime date;
+    // 86400 seconds in a day
+    uint64 secs = timestamp % 86400; // seconds passed today
+    uint64 days = timestamp / 86400; // number of days since Jan 1, 1970
+
+    date.hour = secs / 3600; // gets the hour
+    if (date.hour > 12) {
+        date.hour -= 12; // i don't like military time.
+     }
+    date.minute = (secs % 3600) / 60; // remaining minutes
+    date.second = secs % 60; // remaining seconds
+
+    // unix time starts in 1970
+    date.year = 1970;
+
+    while (1) {
+        int days_per_yr = is_leap(date.year) ? 366 : 365;
+        if (days >= days_per_yr) {
+             // subtract days until it fits within a year
+            days -= days_per_yr; 
+            date.year++;
+        } else {
+            break;
+        }
+    }
+
+    int month = 0;
+    while (1) {
+        int m_days = days_per_month[month];
+        if (month == 1 && is_leap(date.year)) {
+            m_days = 29;
+        }
+        if (days >= m_days) {
+            // subtract days until it fits in a month
+            days -= m_days;
+            month++;
+        } else {
+            break;
+        }
+    }
+    date.month = month + 1; // corrects month 
+    date.day = days + 1; // corrects day
+
+    return date;
+}
+

user/time.h

@@ -0,0 +1,18 @@
+#ifndef TIME_H
+#define TIME_H
+
+#include "kernel/types.h"
+
+typedef struct datetime {
+    int year;
+    int month;
+    int day;
+    int hour;
+    int minute;
+    int second;
+} datetime;
+
+int is_leap(int year);
+datetime to_datetime(uint64 timestamp);
+
+#endif

user/user.h

@@ -24,6 +24,7 @@ int getpid(void);
 char* sys_sbrk(int,int);
 int pause(int);
 int uptime(void);
+int clock(void);
 
 // ulib.c
 int stat(const char*, struct stat*);

user/usys.pl

@@ -42,3 +42,4 @@ sub entry {
 entry("sbrk");
 entry("pause");
 entry("uptime");
+entry("clock");