move history code into history.c

1 files changed, 113 insertions, 0 deletions

diff --git a/util.c b/util.c
index c0f4451..e76ff6b 100644
--- a/util.c
+++ b/util.c
@@ -16,8 +16,16 @@
  * This file contains wrappers to standard functions, which
  * throw exceptions upon failure.
  */
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/file.h>
 #include <stdbool.h>
+#include <unistd.h>
 #include <ctype.h>
+#include <fcntl.h>
+
+#define LINEBUF	32
+#define LINEBUF_MAX	4096
 
 static void *uci_malloc(struct uci_context *ctx, size_t size)
 {
@@ -114,3 +122,108 @@ done:
 	return 0;
 }
 
+
+static void uci_parse_error(struct uci_context *ctx, char *pos, char *reason)
+{
+	struct uci_parse_context *pctx = ctx->pctx;
+
+	pctx->reason = reason;
+	pctx->byte = pos - pctx->buf;
+	UCI_THROW(ctx, UCI_ERR_PARSE);
+}
+
+
+/*
+ * Fetch a new line from the input stream and resize buffer if necessary
+ */
+static void uci_getln(struct uci_context *ctx, int offset)
+{
+	struct uci_parse_context *pctx = ctx->pctx;
+	char *p;
+	int ofs;
+
+	if (pctx->buf == NULL) {
+		pctx->buf = uci_malloc(ctx, LINEBUF);
+		pctx->bufsz = LINEBUF;
+	}
+
+	ofs = offset;
+	do {
+		p = &pctx->buf[ofs];
+		p[ofs] = 0;
+
+		p = fgets(p, pctx->bufsz - ofs, pctx->file);
+		if (!p || !*p)
+			return;
+
+		ofs += strlen(p);
+		if (pctx->buf[ofs - 1] == '\n') {
+			pctx->line++;
+			pctx->buf[ofs - 1] = 0;
+			return;
+		}
+
+		if (pctx->bufsz > LINEBUF_MAX/2)
+			uci_parse_error(ctx, p, "line too long");
+
+		pctx->bufsz *= 2;
+		pctx->buf = uci_realloc(ctx, pctx->buf, pctx->bufsz);
+	} while (1);
+}
+
+/*
+ * open a stream and go to the right position
+ *
+ * note: when opening for write and seeking to the beginning of
+ * the stream, truncate the file
+ */
+static FILE *uci_open_stream(struct uci_context *ctx, const char *filename, int pos, bool write, bool create)
+{
+	struct stat statbuf;
+	FILE *file = NULL;
+	int fd, ret;
+	int mode = (write ? O_RDWR : O_RDONLY);
+
+	if (create)
+		mode |= O_CREAT;
+
+	if (!write && ((stat(filename, &statbuf) < 0) ||
+		((statbuf.st_mode &  S_IFMT) != S_IFREG))) {
+		UCI_THROW(ctx, UCI_ERR_NOTFOUND);
+	}
+
+	fd = open(filename, mode, UCI_FILEMODE);
+	if (fd <= 0)
+		goto error;
+
+	if (flock(fd, (write ? LOCK_EX : LOCK_SH)) < 0)
+		goto error;
+
+	ret = lseek(fd, 0, pos);
+
+	if (ret < 0)
+		goto error;
+
+	file = fdopen(fd, (write ? "w+" : "r"));
+	if (file)
+		goto done;
+
+error:
+	UCI_THROW(ctx, UCI_ERR_IO);
+done:
+	return file;
+}
+
+static void uci_close_stream(FILE *stream)
+{
+	int fd;
+
+	if (!stream)
+		return;
+
+	fd = fileno(stream);
+	flock(fd, LOCK_UN);
+	fclose(stream);
+}
+
+