[flashrom-gerrit] Change in ...flashrom[master]: layout: Add interface to create a dynamically growing layout

[Nico Huber (Code Review)]

Nico Huber has uploaded this change for review. ( https://review.coreboot.org/c/flashrom/+/31014

Change subject: layout: Add interface to create a dynamically growing layout
......................................................................

layout: Add interface to create a dynamically growing layout

Another interim solution until we have a better internal layout
structure (i.e. linked lists).

Change-Id: I0093de58bc7eadc5cd52355937df23c4a6e934ed
Signed-off-by: Nico Huber 
---
M layout.c
M layout.h
2 files changed, 60 insertions(+), 0 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/14/31014/1

diff --git a/layout.c b/layout.c
index c589d17..420a3d9 100644
--- a/layout.c
+++ b/layout.c
@@ -243,3 +243,54 @@
    		 l->entries[i].start, l->entries[i].end, l->entries[i].name);
    }
 }
+
+static size_t dynlayout_size(unsigned int num_entries)
+{
+	return sizeof(struct dynamic_layout) + num_entries * sizeof(struct romentry);
+}
+
+struct flashrom_layout *new_layout(unsigned int num_entries)
+{
+	struct dynamic_layout *const dyn = malloc(dynlayout_size(num_entries));
+	if (!dyn) {
+		msg_gerr("Out of memory!\n");
+		return NULL;
+	}
+
+	memset(dyn, 0x00, sizeof(*dyn));
+	dyn->base.entries = (void *)((uint8_t *)dyn + sizeof(*dyn));
+	dyn->allocated = num_entries;
+
+	return &dyn->base;
+}
+
+int add_layout_entry(struct flashrom_layout **const l, const char *const name,
+		     const size_t start, const size_t end)
+{
+	struct dynamic_layout *dyn;
+
+	if (!*l)
+		*l = new_layout(8);
+	if (!*l)
+		return -1;
+
+	dyn = (void *)*l;
+
+	if (dyn->base.num_entries >= dyn->allocated) {
+		const unsigned int allocate = (dyn->allocated ? : 1) * 2;
+		dyn = realloc(dyn, dynlayout_size(allocate));
+		if (!dyn)
+			return -1;
+		dyn->base.entries = (void *)((uint8_t *)dyn + sizeof(*dyn));
+		dyn->allocated = allocate;
+		*l = (void *)dyn;
+	}
+
+	const unsigned int i = dyn->base.num_entries++;
+	memset(&dyn->base.entries[i], 0x00, sizeof(dyn->base.entries[i]));
+	dyn->base.entries[i].start = start;
+	dyn->base.entries[i].end   = end;
+	snprintf(dyn->base.entries[i].name, sizeof(dyn->base.entries[i].name), "%s", name);
+
+	return 0;
+}
diff --git a/layout.h b/layout.h
index a10cbb4..4227e92 100644
--- a/layout.h
+++ b/layout.h
@@ -54,6 +54,12 @@
    struct romentry entry;
 };

+struct dynamic_layout {
+	struct flashrom_layout base;
+	/* number of (pre)allocated entries */
+	unsigned int allocated;
+};
+
 struct flashrom_layout *get_global_layout(void);
 struct flashrom_flashctx;
 const struct flashrom_layout *get_layout(const struct flashrom_flashctx *const flashctx);
@@ -62,4 +68,7 @@

void report_layout(const struct flashrom_layout *);

+struct flashrom_layout *new_layout(unsigned int num_entries);
+int add_layout_entry(struct flashrom_layout **, const char *name, size_t start, size_t end);
+
 #endif				/* !__LAYOUT_H__ */