Initial prototype.

1 files changed, 62 insertions, 0 deletions

diff --git a/util.h b/util.h
new file mode 100644
index 0000000..3fa5fd0
--- /dev/null
+++ b/util.h
@@ -0,0 +1,62 @@
+#ifndef PNANOE_UTIL_H_
+#define PNANOE_UTIL_H_ 1
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdio.h>
+
+// character buffers
+
+typedef struct cbuf cbuf;
+
+cbuf *cbuf_alloc(size_t initial_size, size_t max_size);
+void cbuf_reset(cbuf *buf);
+void cbuf_put(cbuf *buf, const void *src, size_t len);
+void cbuf_puts(cbuf *buf, const char *src);
+void cbuf_putc(cbuf *buf, int c);
+void cbuf_putf(cbuf *buf, const char *fmt, ...);
+const char *cbuf_get(struct cbuf *buf, size_t *len);
+
+// string lists
+
+struct slist {
+  struct slist *next;
+  char data[];
+};
+
+struct slist *slist_split(const char *str, const char *delim);
+struct slist **slist_append(struct slist **prev, const char *str);
+struct slist *slist_prepend(struct slist *list, const char *str);
+bool slist_contains(const struct slist *list, const char *key);
+
+// miscellaneous utilities
+
+/** Calls `malloc(size)` and aborts if memory allocation failed. */
+void *must_malloc(size_t size);
+
+/** Calls `realloc(ptr, size)` and aborts if memory allocation failed. */
+void *must_realloc(void *ptr, size_t size);
+
+/** Calls `strdup(src)` and aborts if memory allocation failed. */
+char *must_strdup(const char *src);
+
+/**
+ * Reads a full line from \p stream into buffer \p s of size \p size.
+ *
+ * This function is otherwise identical to standard `fgets`, except that if a full line did not fit
+ * in the input buffer, characters are discarded from the stream up to and including the next
+ * newline character. If the file ends before a newline is encountered, a null pointer is
+ * required. This way this function always reads complete lines, which are just truncated if they
+ * don't fit in the buffer.
+ */
+char *fgets_line(char *s, int size, FILE *stream);
+
+/**
+ * Fully writes the contents of \p buf (\p len bytes) into file descriptor \p fd.
+ *
+ * If not all bytes could be written, this function just tries again. It returns 0 on success, or -1
+ * if any of the `write` calls failed with an error.
+ */
+int write_all(int fd, const void *buf, size_t len);
+
+#endif // PNANOE_UTIL_H_