text: expose text save method to calling code

There are cases where it is useful to specify how the file should be saved.

3 files changed, 13 insertions, 11 deletions

diff --git a/sam.c b/sam.c
index 337f8a4..960c670 100644
--- a/sam.c
+++ b/sam.c
@@ -1349,7 +1349,7 @@ static bool cmd_write(Vis *vis, Win *win, Command *cmd, const char *argv[], Curs
 			return false;
 		}
 
-		TextSave *ctx = text_save_begin(text, *name);
+		TextSave *ctx = text_save_begin(text, *name, TEXT_SAVE_AUTO);
 		if (!ctx) {
 			vis_info_show(vis, "Can't write `%s': %s", *name, strerror(errno));
 			return false;
diff --git a/text.c b/text.c
index 2163deb..55957c0 100644
--- a/text.c
+++ b/text.c
@@ -129,11 +129,7 @@ struct TextSave {                  /* used to hold context between text_save_{be
 	char *filename;            /* filename to save to as given to text_save_begin */
 	char *tmpname;             /* temporary name used for atomic rename(2) */
 	int fd;                    /* file descriptor to write data to using text_save_write */
-	enum {
-		TEXT_SAVE_UNKNOWN,
-		TEXT_SAVE_ATOMIC,  /* create a new file, write content, atomically rename(2) over old file */
-		TEXT_SAVE_INPLACE, /* truncate file, overwrite content (any error will result in data loss) */
-	} type;
+	enum TextSaveMethod type;  /* method used to save file */
 };
 
 /* block management */
@@ -997,7 +993,7 @@ static bool text_save_commit_inplace(TextSave *ctx) {
 	return true;
 }
 
-TextSave *text_save_begin(Text *txt, const char *filename) {
+TextSave *text_save_begin(Text *txt, const char *filename, enum TextSaveMethod type) {
 	if (!filename)
 		return NULL;
 	TextSave *ctx = calloc(1, sizeof *ctx);
@@ -1008,11 +1004,11 @@ TextSave *text_save_begin(Text *txt, const char *filename) {
 	if (!(ctx->filename = strdup(filename)))
 		goto err;
 	errno = 0;
-	if (text_save_begin_atomic(ctx))
+	if ((type == TEXT_SAVE_AUTO || type == TEXT_SAVE_ATOMIC) && text_save_begin_atomic(ctx))
 		return ctx;
 	if (errno == ENOSPC)
 		goto err;
-	if (text_save_begin_inplace(ctx))
+	if ((type == TEXT_SAVE_AUTO || type == TEXT_SAVE_INPLACE) && text_save_begin_inplace(ctx))
 		return ctx;
 err:
 	text_save_cancel(ctx);
@@ -1073,7 +1069,7 @@ bool text_save_range(Text *txt, Filerange *range, const char *filename) {
 		text_snapshot(txt);
 		return true;
 	}
-	TextSave *ctx = text_save_begin(txt, filename);
+	TextSave *ctx = text_save_begin(txt, filename, TEXT_SAVE_AUTO);
 	if (!ctx)
 		return false;
 	ssize_t written = text_write_range(txt, range, ctx->fd);
diff --git a/text.h b/text.h
index ee7dd6b..0306a4c 100644
--- a/text.h
+++ b/text.h
@@ -128,6 +128,12 @@ enum TextNewLine {
 enum TextNewLine text_newline_type(Text*);
 const char *text_newline_char(Text*);
 
+enum TextSaveMethod {
+	TEXT_SAVE_AUTO,    /* first try atomic, then fall back to inplace */
+	TEXT_SAVE_ATOMIC,  /* create a new file, write content, atomically rename(2) over old file */
+	TEXT_SAVE_INPLACE, /* truncate file, overwrite content (any error will result in data loss) */
+};
+
 /* save the whole text to the given `filename'. Return true if succesful.
  * In which case an implicit snapshot is taken. The save might associate a
  * new inode to file. */
@@ -138,7 +144,7 @@ bool text_save_range(Text*, Filerange*, const char *file);
  * file ranges. For every call to `text_save_begin` there must be exactly
  * one matching call to either `text_save_commit` or `text_save_cancel`
  * to release the underlying resources. */
-TextSave *text_save_begin(Text*, const char *filename);
+TextSave *text_save_begin(Text*, const char *filename, enum TextSaveMethod);
 ssize_t text_save_write_range(TextSave*, Filerange*);
 /* try committing the changes to disk */
 bool text_save_commit(TextSave*);