libkmod: Read multiple numbers at once

Reduce the FILE overhead by reading as many bytes as possible at once.

Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>
Link: https://github.com/kmod-project/kmod/pull/190
Signed-off-by: Lucas De Marchi <lucas.de.marchi@gmail.com>

diff --git a/libkmod/libkmod-index.c b/libkmod/libkmod-index.c
index da60eda7c663a893a847a9d6d9cd1b41a83564e5..49122bf4234c9d6171d364d5e09d777ff37f7833 100644 (file)
--- a/libkmod/libkmod-index.c
+++ b/libkmod/libkmod-index.c
@@ -178,17 +178,23 @@ static int read_char(FILE *in)
        return ch;
 }
 
-static int read_u32(FILE *in, uint32_t *l)
+static bool read_u32s(FILE *in, uint32_t *l, size_t n)
 {
-       uint32_t val;
+       size_t i;
 
        errno = 0;
-       if (fread(&val, sizeof(uint32_t), 1, in) != 1) {
+       if (fread(l, sizeof(uint32_t), n, in) != n) {
                errno = EINVAL;
-               return -1;
+               return false;
        }
-       *l = ntohl(val);
-       return 1;
+       for (i = 0; i < n; i++)
+               l[i] = ntohl(l[i]);
+       return true;
+}
+
+static inline bool read_u32(FILE *in, uint32_t *l)
+{
+       return read_u32s(in, l, 1);
 }
 
 static ssize_t buf_freadchars(struct strbuf *buf, FILE *in)
@@ -221,7 +227,7 @@ static struct index_node_f *index_read(FILE *in, uint32_t offset)
 {
        struct index_node_f *node = NULL;
        char *prefix = NULL;
-       int i, child_count = 0;
+       size_t child_count = 0;
 
        if ((offset & INDEX_NODE_MASK) == 0)
                return NULL;
@@ -260,9 +266,8 @@ static struct index_node_f *index_read(FILE *in, uint32_t offset)
                node->first = (unsigned char)first;
                node->last = (unsigned char)last;
 
-               for (i = 0; i < child_count; i++)
-                       if (read_u32(in, &node->children[i]) < 0)
-                               goto err;
+               if (!read_u32s(in, node->children, child_count))
+                       goto err;
        } else {
                node = malloc(sizeof(struct index_node_f));
                if (node == NULL)
@@ -279,12 +284,12 @@ static struct index_node_f *index_read(FILE *in, uint32_t offset)
                const char *value;
                unsigned int priority;
 
-               if (read_u32(in, &value_count) < 0)
+               if (!read_u32(in, &value_count))
                        goto err;
 
                strbuf_init(&buf);
                while (value_count--) {
-                       if (read_u32(in, &priority) < 0 || buf_freadchars(&buf, in) < 0) {
+                       if (!read_u32(in, &priority) || buf_freadchars(&buf, in) < 0) {
                                strbuf_release(&buf);
                                goto err;
                        }
@@ -331,10 +336,10 @@ struct index_file *index_file_open(const char *filename)
                return NULL;
        errno = EINVAL;
 
-       if (read_u32(file, &magic) < 0 || magic != INDEX_MAGIC)
+       if (!read_u32(file, &magic) || magic != INDEX_MAGIC)
                goto err;
 
-       if (read_u32(file, &version) < 0 || version >> 16 != INDEX_VERSION_MAJOR)
+       if (!read_u32(file, &version) || version >> 16 != INDEX_VERSION_MAJOR)
                goto err;
 
        new = malloc(sizeof(struct index_file));
@@ -342,7 +347,7 @@ struct index_file *index_file_open(const char *filename)
                goto err;
 
        new->file = file;
-       if (read_u32(new->file, &new->root_offset) < 0) {
+       if (!read_u32(new->file, &new->root_offset)) {
                free(new);
                goto err;
        }