Merge pull request #7 from Richard-Qin-001/dev/shell

Important: License changed from MIT to GPL.

1 files changed, 0 insertions, 1127 deletions

diff --git a/stdlib/stdio.c b/stdlib/stdio.c
deleted file mode 100644
index aa13e25..0000000
--- a/stdlib/stdio.c
+++ /dev/null
@@ -1,1127 +0,0 @@
-#include "stdio.h"
-
-/* Include STB Sprintf Implementation */
-#define STB_SPRINTF_IMPLEMENTATION
-#include "stb_sprintf.h"
-
-/*  Syscall Implementation  */
-
-const int64 STDIN_FD = 0;
-const int64 STDOUT_FD = 1;
-const int64 STDERR_FD = 2;
-
-#if defined(__x86_64__)
-
-const int64 SYS_read = 0;
-const int64 SYS_write = 1;
-const int64 SYS_open = 2;
-const int64 SYS_close = 3;
-const int64 SYS_lseek = 8;
-
-int64 write(int64 fd, const char *buf, uint64 count)
-{
-    int64 ret;
-    __asm__ volatile("syscall" : "=a"(ret) : "a"(SYS_write), "D"(fd), "S"(buf), "d"(count) : "rcx", "r11", "memory");
-    return ret;
-}
-int64 read(int64 fd, char *buf, uint64 count)
-{
-    int64 ret;
-    __asm__ volatile("syscall" : "=a"(ret) : "a"(SYS_read), "D"(fd), "S"(buf), "d"(count) : "rcx", "r11", "memory");
-    return ret;
-}
-int64 open(const char *path, int flags, int mode)
-{
-    int64 ret;
-    __asm__ volatile("syscall" : "=a"(ret) : "a"(SYS_open), "D"(path), "S"(flags), "d"(mode) : "rcx", "r11", "memory");
-    return ret;
-}
-int64 close(int64 fd)
-{
-    int64 ret;
-    __asm__ volatile("syscall" : "=a"(ret) : "a"(SYS_close), "D"(fd) : "rcx", "r11", "memory");
-    return ret;
-}
-int64 lseek(int64 fd, int64 offset, int whence)
-{
-    int64 ret;
-    __asm__ volatile("syscall" : "=a"(ret) : "a"(SYS_lseek), "D"(fd), "S"(offset), "d"(whence) : "rcx", "r11", "memory");
-    return ret;
-}
-
-#elif defined(__riscv)
-
-const int64 SYS_read = 63;
-const int64 SYS_write = 64;
-const int64 SYS_open = 56; // openat
-const int64 SYS_close = 57;
-const int64 SYS_lseek = 62;
-
-int64 write(int64 fd, const char *buf, uint64 count)
-{
-    register int64 a7 asm("a7") = SYS_write;
-    register int64 a0 asm("a0") = fd;
-    register int64 a1 asm("a1") = (int64)buf;
-    register int64 a2 asm("a2") = count;
-    __asm__ volatile("ecall" : "+r"(a0) : "r"(a7), "r"(a0), "r"(a1), "r"(a2) : "memory");
-    return a0;
-}
-int64 read(int64 fd, char *buf, uint64 count)
-{
-    register int64 a7 asm("a7") = SYS_read;
-    register int64 a0 asm("a0") = fd;
-    register int64 a1 asm("a1") = (int64)buf;
-    register int64 a2 asm("a2") = count;
-    __asm__ volatile("ecall" : "+r"(a0) : "r"(a7), "r"(a0), "r"(a1), "r"(a2) : "memory");
-    return a0;
-}
-int64 open(const char *path, int flags, int mode)
-{
-    register int64 a7 asm("a7") = SYS_open;
-    register int64 a0 asm("a0") = -100; // AT_FDCWD
-    register int64 a1 asm("a1") = (int64)path;
-    register int64 a2 asm("a2") = flags;
-    register int64 a3 asm("a3") = mode;
-    __asm__ volatile("ecall" : "+r"(a0) : "r"(a7), "r"(a0), "r"(a1), "r"(a2), "r"(a3) : "memory");
-    return a0;
-}
-int64 close(int64 fd)
-{
-    register int64 a7 asm("a7") = SYS_close;
-    register int64 a0 asm("a0") = fd;
-    __asm__ volatile("ecall" : "+r"(a0) : "r"(a7), "r"(a0) : "memory");
-    return a0;
-}
-int64 lseek(int64 fd, int64 offset, int whence)
-{
-    register int64 a7 asm("a7") = SYS_lseek;
-    register int64 a0 asm("a0") = fd;
-    register int64 a1 asm("a1") = offset;
-    register int64 a2 asm("a2") = whence;
-    __asm__ volatile("ecall" : "+r"(a0) : "r"(a7), "r"(a0), "r"(a1), "r"(a2) : "memory");
-    return a0;
-}
-
-#else
-#error "Architecture not supported"
-#endif
-
-/*  Memory and String Functions  */
-
-void *memset(void *dst, int c, uint64 n)
-{
-    char *cdst = (char *)dst;
-    for (uint64 i = 0; i < n; i++)
-        cdst[i] = (char)c;
-    return dst;
-}
-
-void *memmove(void *vdst, const void *vsrc, uint64 n)
-{
-    char *dst = (char *)vdst;
-    const char *src = (const char *)vsrc;
-    if (dst == src)
-        return vdst;
-    if (src > dst)
-    {
-        while (n--)
-            *dst++ = *src++;
-    }
-    else
-    {
-        dst += n;
-        src += n;
-        while (n-- > 0)
-            *--dst = *--src;
-    }
-    return vdst;
-}
-
-void *memcpy(void *vdst, const void *vsrc, uint64 n) { return memmove(vdst, vsrc, n); }
-
-int memcmp(const void *s1, const void *s2, uint64 n)
-{
-    const unsigned char *p1 = (const unsigned char *)s1;
-    const unsigned char *p2 = (const unsigned char *)s2;
-    while (n--)
-    {
-        if (*p1 != *p2)
-            return *p1 - *p2;
-        p1++;
-        p2++;
-    }
-    return 0;
-}
-
-uint64 strlen(const char *s)
-{
-    const char *p = s;
-    while (*p)
-        p++;
-    return (uint64)(p - s);
-}
-
-char *strcpy(char *dst, const char *src)
-{
-    char *os = dst;
-    while ((*dst++ = *src++) != 0)
-        ;
-    return os;
-}
-
-char *strcat(char *dst, const char *src)
-{
-    char *os = dst;
-    while (*dst)
-        dst++;
-    while ((*dst++ = *src++) != 0)
-        ;
-    return os;
-}
-
-int strcmp(const char *p, const char *q)
-{
-    while (*p && *p == *q)
-    {
-        p++;
-        q++;
-    }
-    return (int)((unsigned char)*p - (unsigned char)*q);
-}
-
-static int isspace(int c)
-{
-    return c == ' ' || c == '\t' || c == '\n' || c == '\v' || c == '\f' || c == '\r';
-}
-
-int64 strtoll(const char *str, char **endptr, int base)
-{
-    const char *s = str;
-    int64 acc = 0;
-    int c;
-    int neg = 0;
-    int any = 0;
-
-    while (isspace(*s))
-        s++;
-    if (*s == '-')
-    {
-        neg = 1;
-        s++;
-    }
-    else if (*s == '+')
-    {
-        s++;
-    }
-
-    if ((base == 0 || base == 16) && *s == '0' && (s[1] == 'x' || s[1] == 'X'))
-    {
-        c = s[2];
-        s += 2;
-        base = 16;
-    }
-    else if (base == 0 && *s == '0')
-    {
-        base = 8;
-    }
-    else if (base == 0)
-    {
-        base = 10;
-    }
-
-    for (;; c = *s++)
-    {
-        c = *s;
-        if (c >= '0' && c <= '9')
-            c -= '0';
-        else if (c >= 'A' && c <= 'Z')
-            c -= 'A' - 10;
-        else if (c >= 'a' && c <= 'z')
-            c -= 'a' - 10;
-        else
-            break;
-        if (c >= base)
-            break;
-        if (any < 0 || acc > (0x7FFFFFFFFFFFFFFFLL / base))
-            any = -1;
-        else
-        {
-            acc *= base;
-            acc += c;
-            any = 1;
-        }
-    }
-    if (endptr != 0)
-        *endptr = (char *)(any ? s : str);
-    return (neg ? -acc : acc);
-}
-
-/*  Core Formatting Implementation  */
-
-static int _ul_to_str_invert(char *buf, uint64 val, int base, int uppercase)
-{
-    int i = 0;
-    const char *digits = uppercase ? "0123456789ABCDEF" : "0123456789abcdef";
-    if (val == 0)
-    {
-        buf[i++] = '0';
-        return i;
-    }
-    while (val != 0)
-    {
-        buf[i++] = digits[val % base];
-        val /= base;
-    }
-    return i;
-}
-
-typedef struct
-{
-    char *buf;
-    uint64 limit;
-    uint64 written;
-    int fd;
-} _OutContext;
-
-static void _out_char(_OutContext *ctx, char c)
-{
-    if (ctx->fd != -1)
-    {
-        write(ctx->fd, &c, 1);
-        ctx->written++;
-    }
-    else
-    {
-        if (ctx->limit > 0 && ctx->written < ctx->limit - 1)
-        {
-            ctx->buf[ctx->written] = c;
-        }
-        ctx->written++;
-    }
-}
-
-static int _vprintf_core(_OutContext *ctx, const char *format, va_list ap)
-{
-    const char *p = format;
-    char num_buf[32];
-
-    while (*p)
-    {
-        if (*p != '%')
-        {
-            _out_char(ctx, *p++);
-            continue;
-        }
-        p++;
-
-        int flag_left = 0, flag_zero = 0, flag_plus = 0, flag_space = 0, flag_hash = 0;
-        while (1)
-        {
-            if (*p == '-')
-                flag_left = 1;
-            else if (*p == '0')
-                flag_zero = 1;
-            else if (*p == '+')
-                flag_plus = 1;
-            else if (*p == ' ')
-                flag_space = 1;
-            else if (*p == '#')
-                flag_hash = 1;
-            else
-                break;
-            p++;
-        }
-
-        int width = 0;
-        if (*p == '*')
-        {
-            width = va_arg(ap, int);
-            if (width < 0)
-            {
-                flag_left = 1;
-                width = -width;
-            }
-            p++;
-        }
-        else
-        {
-            while (*p >= '0' && *p <= '9')
-            {
-                width = width * 10 + (*p - '0');
-                p++;
-            }
-        }
-
-        int precision = -1;
-        if (*p == '.')
-        {
-            p++;
-            if (*p == '*')
-            {
-                precision = va_arg(ap, int);
-                p++;
-            }
-            else
-            {
-                precision = 0;
-                while (*p >= '0' && *p <= '9')
-                {
-                    precision = precision * 10 + (*p - '0');
-                    p++;
-                }
-            }
-        }
-
-        int len_mod = 0;
-        if (*p == 'l')
-        {
-            len_mod = 1;
-            p++;
-            if (*p == 'l')
-            {
-                len_mod = 2;
-                p++;
-            }
-        }
-        else if (*p == 'z')
-        {
-            len_mod = 2;
-            p++;
-        }
-
-        char spec = *p++;
-        if (!spec)
-            break;
-
-        if (spec == 'd' || spec == 'i' || spec == 'u' || spec == 'x' || spec == 'X' || spec == 'p')
-        {
-            uint64 val;
-            int is_signed = (spec == 'd' || spec == 'i');
-            int base = (spec == 'x' || spec == 'X' || spec == 'p') ? 16 : 10;
-
-            if (spec == 'p')
-                val = (uint64)va_arg(ap, void *);
-            else if (len_mod == 2)
-                val = is_signed ? (uint64)va_arg(ap, int64) : va_arg(ap, uint64);
-            else if (len_mod == 1)
-                val = is_signed ? (uint64)va_arg(ap, long) : (uint64)va_arg(ap, unsigned long);
-            else
-                val = is_signed ? (uint64)((int64)va_arg(ap, int)) : (uint64)va_arg(ap, uint32);
-
-            char sign_char = 0;
-            if (is_signed)
-            {
-                int64 sval = (int64)val;
-                if (sval < 0)
-                {
-                    sign_char = '-';
-                    val = (uint64)(-sval);
-                }
-                else if (flag_plus)
-                    sign_char = '+';
-                else if (flag_space)
-                    sign_char = ' ';
-            }
-
-            int digit_len = _ul_to_str_invert(num_buf, val, base, (spec == 'X'));
-            if (precision >= 0)
-                flag_zero = 0;
-            int prec_zeros = (precision > digit_len) ? precision - digit_len : 0;
-            if (precision == 0 && val == 0)
-                digit_len = 0;
-
-            int prefix_len = sign_char ? 1 : 0;
-            char *prefix_str = NULL;
-            if (spec == 'p' || (flag_hash && val != 0 && (spec == 'x' || spec == 'X')))
-            {
-                prefix_str = (spec == 'X') ? "0X" : "0x";
-                prefix_len += 2;
-            }
-
-            int padding = (width > prefix_len + prec_zeros + digit_len) ? width - (prefix_len + prec_zeros + digit_len) : 0;
-
-            if (!flag_left && !flag_zero)
-                for (int i = 0; i < padding; i++)
-                    _out_char(ctx, ' ');
-            if (sign_char)
-                _out_char(ctx, sign_char);
-            if (prefix_str)
-            {
-                _out_char(ctx, prefix_str[0]);
-                _out_char(ctx, prefix_str[1]);
-            }
-            int total_zeros = prec_zeros + ((flag_zero && !flag_left) ? padding : 0);
-            for (int i = 0; i < total_zeros; i++)
-                _out_char(ctx, '0');
-            for (int i = digit_len - 1; i >= 0; i--)
-                _out_char(ctx, num_buf[i]);
-            if (flag_left)
-                for (int i = 0; i < padding; i++)
-                    _out_char(ctx, ' ');
-        }
-        else if (spec == 'f' || spec == 'F' || spec == 'e' || spec == 'E' || spec == 'g' || spec == 'G')
-        {
-            char fmt_tmp[32];
-            int f_idx = 0;
-            fmt_tmp[f_idx++] = '%';
-            if (flag_left)
-                fmt_tmp[f_idx++] = '-';
-            if (flag_zero)
-                fmt_tmp[f_idx++] = '0';
-            if (flag_plus)
-                fmt_tmp[f_idx++] = '+';
-            if (flag_space)
-                fmt_tmp[f_idx++] = ' ';
-            if (flag_hash)
-                fmt_tmp[f_idx++] = '#';
-            if (width > 0)
-                f_idx += sprintf(&fmt_tmp[f_idx], "%d", width);
-            if (precision >= 0)
-                f_idx += sprintf(&fmt_tmp[f_idx], ".%d", precision);
-            fmt_tmp[f_idx++] = spec;
-            fmt_tmp[f_idx] = '\0';
-            double f_val = va_arg(ap, double);
-            char f_buf[128];
-            stbsp_snprintf(f_buf, sizeof(f_buf), fmt_tmp, f_val);
-            for (int i = 0; f_buf[i] != '\0'; i++)
-                _out_char(ctx, f_buf[i]);
-        }
-        else if (spec == 's')
-        {
-            const char *s = va_arg(ap, char *);
-            if (!s)
-                s = "(null)";
-            int len = 0;
-            const char *tmp = s;
-            while (*tmp && (precision < 0 || len < precision))
-            {
-                tmp++;
-                len++;
-            }
-            int padding = (width > len) ? width - len : 0;
-            if (!flag_left)
-                for (int i = 0; i < padding; i++)
-                    _out_char(ctx, ' ');
-            for (int i = 0; i < len; i++)
-                _out_char(ctx, s[i]);
-            if (flag_left)
-                for (int i = 0; i < padding; i++)
-                    _out_char(ctx, ' ');
-        }
-        else if (spec == 'c')
-        {
-            char c = (char)va_arg(ap, int);
-            int padding = (width > 1) ? width - 1 : 0;
-            if (!flag_left)
-                for (int i = 0; i < padding; i++)
-                    _out_char(ctx, ' ');
-            _out_char(ctx, c);
-            if (flag_left)
-                for (int i = 0; i < padding; i++)
-                    _out_char(ctx, ' ');
-        }
-        else
-        {
-            _out_char(ctx, '%');
-            if (spec != '%')
-                _out_char(ctx, spec);
-        }
-    }
-    return (int)ctx->written;
-}
-
-int vsnprintf(char *str, uint64 size, const char *format, va_list ap)
-{
-    _OutContext ctx;
-    ctx.buf = str;
-    ctx.limit = size;
-    ctx.written = 0;
-    ctx.fd = -1;
-    _vprintf_core(&ctx, format, ap);
-    if (size > 0)
-    {
-        if (ctx.written < size)
-            str[ctx.written] = '\0';
-        else
-            str[size - 1] = '\0';
-    }
-    return (int)ctx.written;
-}
-int snprintf(char *str, uint64 size, const char *format, ...)
-{
-    va_list ap;
-    va_start(ap, format);
-    int ret = vsnprintf(str, size, format, ap);
-    va_end(ap);
-    return ret;
-}
-int sprintf(char *str, const char *format, ...)
-{
-    va_list ap;
-    va_start(ap, format);
-    int ret = vsnprintf(str, (uint64)-1, format, ap);
-    va_end(ap);
-    return ret;
-}
-int printf(const char *format, ...)
-{
-    va_list ap;
-    va_start(ap, format);
-    _OutContext ctx;
-    ctx.buf = NULL;
-    ctx.limit = 0;
-    ctx.written = 0;
-    ctx.fd = STDOUT_FD;
-    _vprintf_core(&ctx, format, ap);
-    va_end(ap);
-    return (int)ctx.written;
-}
-
-/*  Core Function Implementation  */
-
-typedef struct
-{
-    const char *buf;
-    int fd;
-    uint64 pos;
-    int ungotten;
-} _InContext;
-
-static int _in_char(_InContext *ctx)
-{
-    if (ctx->ungotten >= 0)
-    {
-        int c = ctx->ungotten;
-        ctx->ungotten = -1;
-        return c;
-    }
-    if (ctx->fd == -1)
-    {
-        if (ctx->buf[ctx->pos] == '\0')
-            return -1;
-        return (unsigned char)ctx->buf[ctx->pos++];
-    }
-    char c;
-    if (read(ctx->fd, &c, 1) == 1)
-        return (unsigned char)c;
-    return -1;
-}
-
-static void _unget_char(_InContext *ctx, int c)
-{
-    if (c != -1)
-        ctx->ungotten = c;
-}
-static void _skip_space(_InContext *ctx)
-{
-    int c;
-    while ((c = _in_char(ctx)) != -1)
-    {
-        if (!isspace(c))
-        {
-            _unget_char(ctx, c);
-            break;
-        }
-    }
-}
-
-static double _simple_strtod(const char *str, char **endptr)
-{
-    double val = 0.0;
-    int sign = 1;
-    if (*str == '-')
-    {
-        sign = -1;
-        str++;
-    }
-    else if (*str == '+')
-        str++;
-    while (*str >= '0' && *str <= '9')
-    {
-        val = val * 10.0 + (*str - '0');
-        str++;
-    }
-    if (*str == '.')
-    {
-        str++;
-        double div = 10.0;
-        while (*str >= '0' && *str <= '9')
-        {
-            val += (*str - '0') / div;
-            div *= 10.0;
-            str++;
-        }
-    }
-    if (*str == 'e' || *str == 'E')
-    {
-        str++;
-        int esign = 1;
-        if (*str == '-')
-        {
-            esign = -1;
-            str++;
-        }
-        else if (*str == '+')
-            str++;
-        int eval = 0;
-        while (*str >= '0' && *str <= '9')
-        {
-            eval = eval * 10 + (*str - '0');
-            str++;
-        }
-        double p = 1.0;
-        while (eval--)
-            p *= 10.0;
-        if (esign == 1)
-            val *= p;
-        else
-            val /= p;
-    }
-    if (endptr)
-        *endptr = (char *)str;
-    return sign * val;
-}
-
-static int _vscanf_core(_InContext *ctx, const char *format, va_list ap)
-{
-    int assigned = 0;
-    const char *p = format;
-    while (*p)
-    {
-        if (isspace(*p))
-        {
-            _skip_space(ctx);
-            while (isspace(*p))
-                p++;
-            continue;
-        }
-        if (*p != '%')
-        {
-            _skip_space(ctx);
-            int c = _in_char(ctx);
-            if (c != *p)
-            {
-                _unget_char(ctx, c);
-                return assigned;
-            }
-            p++;
-            continue;
-        }
-        p++;
-        int suppress = 0;
-        if (*p == '*')
-        {
-            suppress = 1;
-            p++;
-        }
-        int width = -1;
-        while (*p >= '0' && *p <= '9')
-        {
-            if (width == -1)
-                width = 0;
-            width = width * 10 + (*p - '0');
-            p++;
-        }
-        int len_mod = 0;
-        if (*p == 'l')
-        {
-            len_mod = 1;
-            p++;
-            if (*p == 'l')
-            {
-                len_mod = 2;
-                p++;
-            }
-        }
-        else if (*p == 'h')
-        {
-            p++;
-            if (*p == 'h')
-                p++;
-        }
-        char spec = *p++;
-        if (!spec)
-            break;
-
-        if (spec == 'd' || spec == 'i' || spec == 'u' || spec == 'x')
-        {
-            _skip_space(ctx);
-            char num_buf[64];
-            int i = 0, c = _in_char(ctx);
-            if (c == '-' || c == '+')
-            {
-                num_buf[i++] = (char)c;
-                c = _in_char(ctx);
-            }
-            int base = (spec == 'x') ? 16 : (spec == 'i' ? 0 : 10);
-            while (c != -1 && i < 63)
-            {
-                int digit = (c >= '0' && c <= '9');
-                int hex = (base == 16 || base == 0) && ((c >= 'a' && c <= 'f') || (c >= 'A' && c <= 'F'));
-                int x = (c == 'x' || c == 'X');
-                if (base == 0 && i == 1 && num_buf[0] == '0' && x)
-                    base = 16;
-                if (width > 0 && i >= width)
-                    break;
-                if (digit || hex || x)
-                {
-                    num_buf[i++] = (char)c;
-                    c = _in_char(ctx);
-                }
-                else
-                    break;
-            }
-            num_buf[i] = '\0';
-            _unget_char(ctx, c);
-            if (i == 0)
-                return assigned;
-            if (!suppress)
-            {
-                int64 val = strtoll(num_buf, NULL, base);
-                if (len_mod == 2)
-                    *va_arg(ap, int64 *) = val;
-                else if (len_mod == 1)
-                    *va_arg(ap, long *) = (long)val;
-                else
-                    *va_arg(ap, int *) = (int)val;
-                assigned++;
-            }
-        }
-        else if (spec == 'f' || spec == 'F' || spec == 'e' || spec == 'E' || spec == 'g' || spec == 'G')
-        {
-            _skip_space(ctx);
-            char num_buf[64];
-            int i = 0, c = _in_char(ctx);
-            if (c == '-' || c == '+')
-            {
-                num_buf[i++] = (char)c;
-                c = _in_char(ctx);
-            }
-            while (c != -1 && i < 63)
-            {
-                if ((c >= '0' && c <= '9') || c == '.' || c == 'e' || c == 'E' || c == '+' || c == '-')
-                {
-                    num_buf[i++] = (char)c;
-                    c = _in_char(ctx);
-                }
-                else
-                    break;
-            }
-            num_buf[i] = '\0';
-            _unget_char(ctx, c);
-            if (i == 0)
-                return assigned;
-            if (!suppress)
-            {
-                double val = _simple_strtod(num_buf, NULL);
-                if (len_mod == 1)
-                    *va_arg(ap, double *) = val;
-                else
-                    *va_arg(ap, float *) = (float)val;
-                assigned++;
-            }
-        }
-        else if (spec == 's')
-        {
-            _skip_space(ctx);
-            char *buf = suppress ? NULL : va_arg(ap, char *);
-            int i = 0, c = _in_char(ctx);
-            while (c != -1 && !isspace(c))
-            {
-                if (width > 0 && i >= width)
-                    break;
-                if (!suppress)
-                    buf[i] = (char)c;
-                i++;
-                c = _in_char(ctx);
-            }
-            if (!suppress)
-                buf[i] = '\0';
-            _unget_char(ctx, c);
-            if (i > 0 && !suppress)
-                assigned++;
-        }
-        else if (spec == 'c')
-        {
-            int count = (width > 0) ? width : 1;
-            char *buf = suppress ? NULL : va_arg(ap, char *);
-            for (int i = 0; i < count; i++)
-            {
-                int c = _in_char(ctx);
-                if (c == -1)
-                    return assigned;
-                if (!suppress)
-                    buf[i] = (char)c;
-            }
-            if (!suppress)
-                assigned++;
-        }
-    }
-    return assigned;
-}
-
-int sscanf(const char *str, const char *format, ...)
-{
-    va_list ap;
-    va_start(ap, format);
-    _InContext ctx;
-    ctx.buf = str;
-    ctx.fd = -1;
-    ctx.pos = 0;
-    ctx.ungotten = -1;
-    int ret = _vscanf_core(&ctx, format, ap);
-    va_end(ap);
-    return ret;
-}
-int scanf(const char *format, ...)
-{
-    va_list ap;
-    va_start(ap, format);
-    _InContext ctx;
-    ctx.buf = NULL;
-    ctx.fd = STDIN_FD;
-    ctx.pos = 0;
-    ctx.ungotten = -1;
-    int ret = _vscanf_core(&ctx, format, ap);
-    va_end(ap);
-    return ret;
-}
-
-/*  FILE Stream Implementation  */
-
-#define O_RDONLY 00
-#define O_WRONLY 01
-#define O_RDWR 02
-#define O_CREAT 0100
-#define O_TRUNC 01000
-#define O_APPEND 02000
-
-#define MAX_FILES 8
-static FILE _file_pool[MAX_FILES];
-static FILE _stdin = {.fd = 0, .used = 1};
-static FILE _stdout = {.fd = 1, .used = 1};
-static FILE _stderr = {.fd = 2, .used = 1};
-
-FILE *stdin = &_stdin;
-FILE *stdout = &_stdout;
-FILE *stderr = &_stderr;
-
-FILE *fopen(const char *filename, const char *mode)
-{
-    int flags = 0;
-    if (strcmp(mode, "r") == 0)
-        flags = O_RDONLY;
-    else if (strcmp(mode, "w") == 0)
-        flags = O_WRONLY | O_CREAT | O_TRUNC;
-    else if (strcmp(mode, "a") == 0)
-        flags = O_WRONLY | O_CREAT | O_APPEND;
-    else if (strcmp(mode, "r+") == 0)
-        flags = O_RDWR;
-    else
-        return NULL;
-
-    FILE *f = NULL;
-    for (int i = 0; i < MAX_FILES; i++)
-        if (!_file_pool[i].used)
-        {
-            f = &_file_pool[i];
-            break;
-        }
-    if (!f)
-        return NULL;
-
-    int64 fd = open(filename, flags, 0666);
-    if (fd < 0)
-        return NULL;
-    f->fd = (int)fd;
-    f->flags = flags;
-    f->error = 0;
-    f->eof = 0;
-    f->used = 1;
-    return f;
-}
-
-int fclose(FILE *stream)
-{
-    if (!stream || !stream->used)
-        return -1;
-    if (stream == stdin || stream == stdout || stream == stderr)
-        return 0;
-    close(stream->fd);
-    stream->used = 0;
-    stream->fd = -1;
-    return 0;
-}
-
-int fflush(FILE *stream) { return 0; }
-
-int fprintf(FILE *stream, const char *format, ...)
-{
-    if (!stream)
-        return -1;
-    va_list ap;
-    va_start(ap, format);
-    _OutContext ctx;
-    ctx.buf = NULL;
-    ctx.limit = 0;
-    ctx.written = 0;
-    ctx.fd = stream->fd;
-    _vprintf_core(&ctx, format, ap);
-    va_end(ap);
-    return (int)ctx.written;
-}
-
-int fscanf(FILE *stream, const char *format, ...)
-{
-    if (!stream)
-        return -1;
-    va_list ap;
-    va_start(ap, format);
-    _InContext ctx;
-    ctx.buf = NULL;
-    ctx.fd = stream->fd;
-    ctx.pos = 0;
-    ctx.ungotten = -1;
-    int ret = _vscanf_core(&ctx, format, ap);
-    va_end(ap);
-    return ret;
-}
-
-int fputc(int c, FILE *stream)
-{
-    if (!stream)
-        return -1;
-    char ch = (char)c;
-    write(stream->fd, &ch, 1);
-    return c;
-}
-
-int fputs(const char *s, FILE *stream)
-{
-    if (!stream)
-        return -1;
-    write(stream->fd, s, strlen(s));
-    return 0;
-}
-
-int fgetc(FILE *stream)
-{
-    if (!stream)
-        return -1;
-    char c;
-    if (read(stream->fd, &c, 1) == 1)
-        return (unsigned char)c;
-    stream->eof = 1;
-    return -1;
-}
-
-char *fgets(char *str, int n, FILE *stream)
-{
-    if (!stream || !stream->used || n <= 0)
-        return NULL;
-    int i = 0, c;
-    while (i < n - 1)
-    {
-        c = fgetc(stream);
-        if (c == -1)
-        {
-            if (i == 0)
-                return NULL;
-            break;
-        }
-        str[i++] = (char)c;
-        if (c == '\n')
-            break;
-    }
-    str[i] = '\0';
-    return str;
-}
-
-uint64 fread(void *ptr, uint64 size, uint64 nmemb, FILE *stream)
-{
-    if (!stream || !stream->used || !ptr || size == 0 || nmemb == 0)
-        return 0;
-    uint64 total = size * nmemb, read_bytes = 0;
-    char *p = (char *)ptr;
-    while (read_bytes < total)
-    {
-        int64 ret = read(stream->fd, p + read_bytes, total - read_bytes);
-        if (ret > 0)
-            read_bytes += ret;
-        else if (ret == 0)
-        {
-            stream->eof = 1;
-            break;
-        }
-        else
-        {
-            stream->error = 1;
-            break;
-        }
-    }
-    return read_bytes / size;
-}
-
-uint64 fwrite(const void *ptr, uint64 size, uint64 nmemb, FILE *stream)
-{
-    if (!stream || !stream->used || !ptr || size == 0 || nmemb == 0)
-        return 0;
-    uint64 total = size * nmemb, written = 0;
-    const char *p = (const char *)ptr;
-    while (written < total)
-    {
-        int64 ret = write(stream->fd, p + written, total - written);
-        if (ret > 0)
-            written += ret;
-        else
-        {
-            stream->error = 1;
-            break;
-        }
-    }
-    return written / size;
-}
-
-int fseek(FILE *stream, long offset, int whence)
-{
-    if (!stream || !stream->used)
-        return -1;
-    stream->eof = 0;
-    if (lseek(stream->fd, offset, whence) < 0)
-    {
-        stream->error = 1;
-        return -1;
-    }
-    return 0;
-}
-long ftell(FILE *stream)
-{
-    if (!stream || !stream->used)
-        return -1L;
-    int64 ret = lseek(stream->fd, 0, SEEK_CUR);
-    if (ret < 0)
-    {
-        stream->error = 1;
-        return -1L;
-    }
-    return (long)ret;
-}
-void rewind(FILE *stream)
-{
-    if (stream)
-    {
-        fseek(stream, 0, SEEK_SET);
-        stream->error = 0;
-    }
-}
-
-int feof(FILE *stream) { return (stream && stream->used) ? stream->eof : 1; }
-int ferror(FILE *stream) { return (stream && stream->used) ? stream->error : 1; }
-void clearerr(FILE *stream)
-{
-    if (stream && stream->used)
-    {
-        stream->error = 0;
-        stream->eof = 0;
-    }
-}
\ No newline at end of file