First primitive cut of ccanlint

[ccan] / ccan_tools / ccanlint / get_file_lines.c

diff --git a/ccan_tools/ccanlint/get_file_lines.c b/ccan_tools/ccanlint/get_file_lines.c
new file mode 100644 (file)
index 0000000..e9ef302
--- /dev/null
+++ b/ccan_tools/ccanlint/get_file_lines.c
@@ -0,0 +1,85 @@
+#include "get_file_lines.h"
+#include <talloc/talloc.h>
+#include <string/string.h>
+#include <noerr/noerr.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <err.h>
+#include <dirent.h>
+
+static void *grab_fd(const void *ctx, int fd)
+{
+       int ret;
+       unsigned int max = 16384, size = 0;
+       char *buffer;
+
+       buffer = talloc_array(ctx, char, max+1);
+       while ((ret = read(fd, buffer + size, max - size)) > 0) {
+               size += ret;
+               if (size == max)
+                       buffer = talloc_realloc(ctx, buffer, char, max*=2 + 1);
+       }
+       if (ret < 0) {
+               talloc_free(buffer);
+               buffer = NULL;
+       } else
+               buffer[size] = '\0';
+
+       return buffer;
+}
+
+/* This version adds one byte (for nul term) */
+static void *grab_file(const void *ctx, const char *filename)
+{
+       int fd;
+       char *buffer;
+
+       if (streq(filename, "-"))
+               fd = dup(STDIN_FILENO);
+       else
+               fd = open(filename, O_RDONLY, 0);
+
+       if (fd < 0)
+               return NULL;
+
+       buffer = grab_fd(ctx, fd);
+       close_noerr(fd);
+       return buffer;
+}
+
+/* This is a dumb one which copies.  We could mangle instead. */
+static char **split(const void *ctx, const char *text, const char *delims,
+                   unsigned int *nump)
+{
+       char **lines = NULL;
+       unsigned int max = 64, num = 0;
+
+       lines = talloc_array(ctx, char *, max+1);
+
+       while (*text != '\0') {
+               unsigned int len = strcspn(text, delims);
+               lines[num] = talloc_array(lines, char, len + 1);
+               memcpy(lines[num], text, len);
+               lines[num][len] = '\0';
+               text += len;
+               text += strspn(text, delims);
+               if (++num == max)
+                       lines = talloc_realloc(ctx, lines, char *, max*=2 + 1);
+       }
+       lines[num] = NULL;
+       if (nump)
+               *nump = num;
+       return lines;
+}
+
+char **get_file_lines(void *ctx, const char *name, unsigned int *num_lines)
+{
+       char *buffer = grab_file(ctx, name);
+
+       if (!buffer)
+               err(1, "Getting file %s", name);
+
+       return split(buffer, buffer, "\n", num_lines);
+}