1 files changed, 107 insertions, 0 deletions
diff --git a/src/basic/io-util.h b/src/basic/io-util.h
new file mode 100644
index 0000000..3afb134
--- /dev/null
+++ b/src/basic/io-util.h
@@ -0,0 +1,107 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+#pragma once
+
+#include <poll.h>
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+#include <sys/uio.h>
+
+#include "macro.h"
+#include "time-util.h"
+
+int flush_fd(int fd);
+
+ssize_t loop_read(int fd, void *buf, size_t nbytes, bool do_poll);
+int loop_read_exact(int fd, void *buf, size_t nbytes, bool do_poll);
+int loop_write(int fd, const void *buf, size_t nbytes, bool do_poll);
+
+int pipe_eof(int fd);
+
+int ppoll_usec(struct pollfd *fds, size_t nfds, usec_t timeout);
+int fd_wait_for_event(int fd, int event, usec_t timeout);
+
+ssize_t sparse_write(int fd, const void *p, size_t sz, size_t run_length);
+
+static inline size_t IOVEC_TOTAL_SIZE(const struct iovec *i, size_t n) {
+        size_t r = 0;
+
+        for (size_t j = 0; j < n; j++)
+                r += i[j].iov_len;
+
+        return r;
+}
+
+static inline bool IOVEC_INCREMENT(struct iovec *i, size_t n, size_t k) {
+        /* Returns true if there is nothing else to send (bytes written cover all of the iovec),
+         * false if there's still work to do. */
+
+        for (size_t j = 0; j < n; j++) {
+                size_t sub;
+
+                if (i[j].iov_len == 0)
+                        continue;
+                if (k == 0)
+                        return false;
+
+                sub = MIN(i[j].iov_len, k);
+                i[j].iov_len -= sub;
+                i[j].iov_base = (uint8_t*) i[j].iov_base + sub;
+                k -= sub;
+        }
+
+        assert(k == 0); /* Anything else would mean that we wrote more bytes than available,
+                         * or the kernel reported writing more bytes than sent. */
+        return true;
+}
+
+static inline bool FILE_SIZE_VALID(uint64_t l) {
+        /* ftruncate() and friends take an unsigned file size, but actually cannot deal with file sizes larger than
+         * 2^63 since the kernel internally handles it as signed value. This call allows checking for this early. */
+
+        return (l >> 63) == 0;
+}
+
+static inline bool FILE_SIZE_VALID_OR_INFINITY(uint64_t l) {
+
+        /* Same as above, but allows one extra value: -1 as indication for infinity. */
+
+        if (l == UINT64_MAX)
+                return true;
+
+        return FILE_SIZE_VALID(l);
+
+}
+
+#define IOVEC_INIT(base, len) { .iov_base = (base), .iov_len = (len) }
+#define IOVEC_MAKE(base, len) (struct iovec) IOVEC_INIT(base, len)
+#define IOVEC_INIT_STRING(string) IOVEC_INIT((char*) string, strlen(string))
+#define IOVEC_MAKE_STRING(string) (struct iovec) IOVEC_INIT_STRING(string)
+
+char* set_iovec_string_field(struct iovec *iovec, size_t *n_iovec, const char *field, const char *value);
+char* set_iovec_string_field_free(struct iovec *iovec, size_t *n_iovec, const char *field, char *value);
+
+struct iovec_wrapper {
+        struct iovec *iovec;
+        size_t count;
+};
+
+struct iovec_wrapper *iovw_new(void);
+struct iovec_wrapper *iovw_free(struct iovec_wrapper *iovw);
+struct iovec_wrapper *iovw_free_free(struct iovec_wrapper *iovw);
+void iovw_free_contents(struct iovec_wrapper *iovw, bool free_vectors);
+
+int iovw_put(struct iovec_wrapper *iovw, void *data, size_t len);
+static inline int iovw_consume(struct iovec_wrapper *iovw, void *data, size_t len) {
+        /* Move data into iovw or free on error */
+        int r = iovw_put(iovw, data, len);
+        if (r < 0)
+                free(data);
+        return r;
+}
+
+int iovw_put_string_field(struct iovec_wrapper *iovw, const char *field, const char *value);
+int iovw_put_string_field_free(struct iovec_wrapper *iovw, const char *field, char *value);
+void iovw_rebase(struct iovec_wrapper *iovw, char *old, char *new);
+size_t iovw_size(struct iovec_wrapper *iovw);