tal/grab_file: new module

[ccan] / ccan / tal / grab_file / grab_file.h

diff --git a/ccan/tal/grab_file/grab_file.h b/ccan/tal/grab_file/grab_file.h
new file mode 100644 (file)
index 0000000..03bf32a
--- /dev/null
+++ b/ccan/tal/grab_file/grab_file.h
@@ -0,0 +1,60 @@
+/* Licensed under LGPLv2+ - see LICENSE file for details */
+#ifndef CCAN_TAL_GRAB_FILE_H
+#define CCAN_TAL_GRAB_FILE_H
+#include <stdio.h> // For size_t
+
+/**
+ * grab_fd - read all of a file descriptor into memory
+ * @ctx: the context to tallocate from (often NULL)
+ * @fd: the file descriptor to read from
+ *
+ * This function reads from the given file descriptor until no more
+ * input is available.  The content is talloced off @ctx, and the
+ * tal_count() is the size in bytes plus one: for convenience, the
+ * byte after the end of the content will always be NUL.
+ *
+ * Example:
+ *     #include <ccan/tal/str/str.h>
+ *     #include <ccan/tal/tal.h>
+ *     ...
+ *     // Return all of standard input, as lines.
+ *     static char **read_stdin_as_lines(void)
+ *     {
+ *             char **lines, *all;
+ *
+ *             all = grab_fd(NULL, 0);
+ *             if (!all)
+ *                     return NULL;
+ *             lines = tal_strsplit(NULL, all, "\n", STR_EMPTY_OK);
+ *             tal_free(all);
+ *             return lines;
+ *     }
+ */
+void *grab_fd(const void *ctx, int fd);
+
+/**
+ * grab_file - read all of a file (or stdin) into memory
+ * @ctx: the context to tallocate from (often NULL)
+ * @filename: the file to read (NULL for stdin)
+ *
+ * This function reads from the given file until no more input is
+ * available.  The content is talloced off @ctx, and the tal_count()
+ * is the size in bytes plus one: for convenience, the byte after the
+ * end of the content will always be NUL.
+ *
+ * Example:
+ *     // Return all of a given file, as lines.
+ *     static char **read_file_as_lines(const char *filename)
+ *     {
+ *             char **lines, *all;
+ *
+ *             all = grab_file(NULL, filename);
+ *             if (!all)
+ *                     return NULL;
+ *             lines = tal_strsplit(NULL, all, "\n", STR_EMPTY_OK);
+ *             tal_free(all);
+ *             return lines;
+ *     }
+ */
+void *grab_file(const void *ctx, const char *filename);
+#endif /* CCAN_TAL_GRAB_FILE_H */