1 files changed, 164 insertions, 0 deletions
diff --git a/tests/printf.c b/tests/printf.c
new file mode 100644
index 0000000..fc0d68d
--- /dev/null
+++ b/tests/printf.c
@@ -0,0 +1,164 @@
+char  out_buf[4096];
+int   out_pos = 0;
+
+int buf_putc(char c) {
+    out_buf[out_pos] = c;
+    out_pos++;
+    if (out_pos >= 4096) {
+        syscall(1, 1, out_buf, out_pos);
+        out_pos = 0;
+    }
+    return 1;
+}
+
+int buf_flush() {
+    if (out_pos > 0) {
+        syscall(1, 1, out_buf, out_pos);
+        out_pos = 0;
+    }
+    return 0;
+}
+
+
+int my_strlen(char *s) {
+    int n = 0;
+    while (s[n] != 0) { n++; }
+    return n;
+}
+
+int print_str(char *s) {
+    int i = 0;
+    while (s[i] != 0) { buf_putc(s[i]); i++; }
+    return i;
+}
+
+
+int print_int(int n) {
+    char tmp[24];
+    int  len = 0;
+    int  neg = n < 0;
+    if (neg) { buf_putc('-'); n = -n; }
+    if (n == 0) { buf_putc('0'); return neg + 1; }
+    while (n > 0) {
+        tmp[len] = (char)('0' + n % 10);
+        n = n / 10;
+        len++;
+    }
+
+    int i = len - 1;
+    while (i >= 0) { buf_putc(tmp[i]); i--; }
+    return neg + len;
+}
+
+
+int print_hex(int n) {
+    char hex[16] = {'0','1','2','3','4','5','6','7',
+                    '8','9','a','b','c','d','e','f'};
+    if (n == 0) { buf_putc('0'); return 1; }
+    char tmp[18];
+    int  len = 0;
+    int  u = n;
+    while (u != 0) {
+        tmp[len] = hex[u & 15];
+        u = u / 16;
+        len++;
+    }
+    int i = len - 1;
+    while (i >= 0) { buf_putc(tmp[i]); i--; }
+    return len;
+}
+
+
+int my_printf(char *fmt, int a, int b, int c) {
+    int arg_idx = 0;
+    int i = 0;
+    int total = 0;
+    while (fmt[i] != 0) {
+        if (fmt[i] != '%') {
+            buf_putc(fmt[i]);
+            total++;
+            i++;
+            continue;
+        }
+        i++;  /* skip '%' */
+        int arg = arg_idx == 0 ? a : (arg_idx == 1 ? b : c);
+        arg_idx++;
+        if (fmt[i] == 'd') {
+            total += print_int(arg);
+        } else if (fmt[i] == 's') {
+            total += print_str((char*)arg);
+        } else if (fmt[i] == 'c') {
+            buf_putc((char)arg);
+            total++;
+        } else if (fmt[i] == 'x') {
+            total += print_hex(arg);
+        } else if (fmt[i] == '%') {
+            buf_putc('%');
+            total++;
+            arg_idx--;  /* %% doesn't consume an arg */
+        } else {
+            buf_putc('%'); buf_putc(fmt[i]);
+            total += 2;
+        }
+        i++;
+    }
+    return total;
+}
+
+
+int fact(int n) {
+    return n <= 1 ? 1 : n * fact(n - 1);
+}
+
+int fib(int n) {
+    if (n <= 1) return n;
+    return fib(n - 1) + fib(n - 2);
+}
+
+int main() {
+    my_printf("=== JIT printf demo ===\n", 0, 0, 0);
+
+    my_printf("Hello, %s!\n", "world", 0, 0);
+    my_printf("int: %d  neg: %d\n", 42, -7, 0);
+    my_printf("hex: 0x%x\n", 255, 0, 0);
+    my_printf("char: %c\n", 'A', 0, 0);
+    my_printf("percent: 100%%\n", 0, 0, 0);
+
+    my_printf("\nFactorials:\n", 0, 0, 0);
+    int i = 1;
+    while (i <= 8) {
+        my_printf("  %d! = %d\n", i, fact(i), 0);
+        i++;
+    }
+
+    my_printf("\nFibonacci:\n  ", 0, 0, 0);
+    i = 0;
+    while (i < 10) {
+        my_printf("%d ", fib(i), 0, 0);
+        i++;
+    }
+    my_printf("\n", 0, 0, 0);
+
+
+    my_printf("\nCountdown: ", 0, 0, 0);
+    int n = 5;
+    do {
+        my_printf("%d ", n, 0, 0);
+        n--;
+    } while (n > 0);
+    my_printf("\n", 0, 0, 0);
+
+
+    my_printf("Odd 1-9:   ", 0, 0, 0);
+    i = 0;
+    while (i < 10) {
+        i++;
+        if (i % 2 == 0) continue;
+        my_printf("%d ", i, 0, 0);
+        if (i == 9) break;
+    }
+    my_printf("\n", 0, 0, 0);
+
+    buf_flush();
+    return 0;
+}