First commit

1 files changed, 68 insertions, 0 deletions

diff --git a/dynstr.c b/dynstr.c
new file mode 100644
index 0000000..35d47b1
--- /dev/null
+++ b/dynstr.c
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+/*
+   Copyright 2020 Xavier Del Campo Romero
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+      http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+#include "dynstr.h"
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <stddef.h>
+
+void dynstr_init(struct dynstr *const d)
+{
+    memset(d, 0, sizeof *d);
+}
+
+int dynstr_append(struct dynstr *const d, const char *const format, ...)
+{
+    va_list ap;
+
+    va_start(ap, format);
+    const size_t src_len = vsnprintf(NULL, 0, format, ap);
+    size_t new_len;
+    va_end(ap);
+
+    if (!d->str)
+    {
+        new_len = src_len + 1;
+        d->str = calloc(src_len + 1, sizeof *d->str);
+    }
+    else
+    {
+        new_len = d->len + src_len + 1;
+        d->str = realloc(d->str, (d->len + src_len) * sizeof *d->str);
+    }
+
+    if (d->str)
+    {
+        va_start(ap, format);
+        vsprintf(d->str + d->len, format, ap);
+        va_end(ap);
+        d->len += src_len;
+    }
+    else
+    {
+        return 1;
+    }
+
+    return 0;
+}
+
+void dynstr_free(struct dynstr *const d)
+{
+    free(d->str);
+    memset(d, 0, sizeof *d);
+}