1 files changed, 109 insertions, 0 deletions
diff --git a/riscv/riscv-probe/libfemto/std/vsnprintf.c b/riscv/riscv-probe/libfemto/std/vsnprintf.c
new file mode 100644
index 0000000..32dcf3f
--- /dev/null
+++ b/riscv/riscv-probe/libfemto/std/vsnprintf.c
@@ -0,0 +1,109 @@
+// See LICENSE for license details.
+
+#include <stddef.h>
+#include <stdarg.h>
+
+int vsnprintf(char * out, size_t n, const char* s, va_list vl)
+{
+    int format = 0;
+    int longarg = 0;
+    size_t pos = 0;
+    for( ; *s; s++) {
+        if (format) {
+            switch(*s) {
+            case 'l': {
+                longarg = 1;
+                break;
+            }
+            case 'p': {
+                longarg = 1;
+                if (out && pos < n) {
+                    out[pos] = '0';
+                }
+                pos++;
+                if (out && pos < n) {
+                    out[pos] = 'x';
+                }
+                pos++;
+            }
+            case 'x': {
+                long num = longarg ? va_arg(vl, long) : va_arg(vl, int);
+                int hexdigits = 2*(longarg ? sizeof(long) : sizeof(int))-1;
+                for(int i = hexdigits; i >= 0; i--) {
+                    int d = (num >> (4*i)) & 0xF;
+                    if (out && pos < n) {
+                        out[pos] = (d < 10 ? '0'+d : 'a'+d-10);
+                    }
+                    pos++;
+                }
+                longarg = 0;
+                format = 0;
+                break;
+            }
+            case 'd': {
+                long num = longarg ? va_arg(vl, long) : va_arg(vl, int);
+                if (num < 0) {
+                    num = -num;
+                    if (out && pos < n) {
+                        out[pos] = '-';
+                    }
+                    pos++;
+                }
+                long digits = 1;
+                for (long nn = num; nn /= 10; digits++)
+                    ;
+                for (int i = digits-1; i >= 0; i--) {
+                    if (out && pos + i < n) {
+                        out[pos + i] = '0' + (num % 10);
+                    }
+                    num /= 10;
+                }
+                pos += digits;
+                longarg = 0;
+                format = 0;
+                break;
+            }
+            case 's': {
+                const char* s2 = va_arg(vl, const char*);
+                while (*s2) {
+                    if (out && pos < n) {
+                        out[pos] = *s2;
+                    }
+                    pos++;
+                    s2++;
+                }
+                longarg = 0;
+                format = 0;
+                break;
+            }
+            case 'c': {
+                if (out && pos < n) {
+                    out[pos] = (char)va_arg(vl,int);
+                }
+                pos++;
+                longarg = 0;
+                format = 0;
+                break;
+            }
+            default:
+                break;
+            }
+        }
+        else if(*s == '%') {
+          format = 1;
+        }
+        else {
+          if (out && pos < n) {
+            out[pos] = *s;
+          }
+          pos++;
+        }
+    }
+    if (out && pos < n) {
+        out[pos] = 0;
+    }
+    else if (out && n) {
+        out[n-1] = 0;
+    }
+    return pos;
+}