Add a function to modify inplace only a portion of a property..
This is especially useful when the property is an array of values, and you
want to update one of them without changing the DT size.
Acked-by: Simon Glass <sjg@xxxxxxxxxxxx>
Reviewed-by: David Gibson <david@xxxxxxxxxxxxxxxxxxxxx>
Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
---
libfdt/fdt_wip.c | 29 +++++++++++++++++++++++++----
libfdt/libfdt.h | 21 +++++++++++++++++++++
tests/setprop_inplace.c | 10 ++++++++++
tests/testdata.h | 3 +++
4 files changed, 59 insertions(+), 4 deletions(-)
diff --git a/libfdt/fdt_wip.c b/libfdt/fdt_wip.c
index c5bbb68d3273..a6e158d1889a 100644
--- a/libfdt/fdt_wip.c
+++ b/libfdt/fdt_wip.c
@@ -55,21 +55,42 @@
#include "libfdt_internal.h"
+int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
+ const char *name, int namelen,
+ uint32_t idx, const void *val,
+ int len)
+{
+ void *propval;
+ int proplen;
+
+ propval = fdt_getprop_namelen_w(fdt, nodeoffset, name, namelen,
+ &proplen);
+ if (!propval)
+ return proplen;
+
+ if (proplen < (len + idx))
+ return -FDT_ERR_NOSPACE;
+
+ memcpy((unsigned char *)propval + idx, val, len);
+ return 0;
+}
+
int fdt_setprop_inplace(void *fdt, int nodeoffset, const char *name,
const void *val, int len)
{
- void *propval;
+ const void *propval;
int proplen;
- propval = fdt_getprop_w(fdt, nodeoffset, name, &proplen);
+ propval = fdt_getprop(fdt, nodeoffset, name, &proplen);
if (! propval)
return proplen;
if (proplen != len)
return -FDT_ERR_NOSPACE;
- memcpy(propval, val, len);
- return 0;
+ return fdt_setprop_inplace_namelen_partial(fdt, nodeoffset, name,
+ strlen(name), 0,
+ val, len);
}
static void _fdt_nop_region(void *start, int len)
diff --git a/libfdt/libfdt.h b/libfdt/libfdt.h
index 0189350fb32f..e534a34355a4 100644
--- a/libfdt/libfdt.h
+++ b/libfdt/libfdt.h
@@ -1079,6 +1079,27 @@ int fdt_size_cells(const void *fdt, int nodeoffset);
/* Write-in-place functions */
/**********************************************************************/
+/**
+ * fdt_setprop_inplace_namelen_partial - change a property's value,
+ * but not its size
+ * @fdt: pointer to the device tree blob
+ * @nodeoffset: offset of the node whose property to change
+ * @name: name of the property to change
+ * @namelen: number of characters of name to consider
+ * @index: index of the property to change in the array
+ * @val: pointer to data to replace the property value with
+ * @len: length of the property value
+ *
+ * Identical to fdt_setprop_inplace(), but modifies the given property
+ * starting from the given index, and using only the first characters
+ * of the name. It is useful when you want to manipulate only one value of
+ * an array and you have a string that doesn't end with \0.
+ */
+int fdt_setprop_inplace_namelen_partial(void *fdt, int nodeoffset,
+ const char *name, int namelen,
+ uint32_t idx, const void *val,
+ int len);
+
/**
* fdt_setprop_inplace - change a property's value, but not its size
* @fdt: pointer to the device tree blob
diff --git a/tests/setprop_inplace.c b/tests/setprop_inplace.c
index daef182d0b28..80447a0b13ab 100644
--- a/tests/setprop_inplace.c
+++ b/tests/setprop_inplace.c
@@ -83,5 +83,15 @@ int main(int argc, char *argv[])
strp = check_getprop(fdt, 0, "prop-str", xlen+1, xstr);
verbose_printf("New string value is \"%s\"\n", strp);
+ err = fdt_setprop_inplace_namelen_partial(fdt, 0, "compatible",
+ strlen("compatible"), 4,
+ TEST_STRING_4_PARTIAL,
+ strlen(TEST_STRING_4_PARTIAL));
+ if (err)
+ FAIL("Failed to set \"compatible\": %s\n", fdt_strerror(err));
+
+ check_getprop(fdt, 0, "compatible", strlen(TEST_STRING_4_RESULT) + 1,
+ TEST_STRING_4_RESULT);
+
PASS();
}
diff --git a/tests/testdata.h b/tests/testdata.h
index 576974dddee8..3588778ad159 100644
--- a/tests/testdata.h
+++ b/tests/testdata.h
@@ -21,6 +21,9 @@
#define TEST_STRING_2 "nastystring: \a\b\t\n\v\f\r\\\""
#define TEST_STRING_3 "\xde\xad\xbe\xef"
+#define TEST_STRING_4_PARTIAL "foobar"
+#define TEST_STRING_4_RESULT "testfoobar"
+
#define TEST_CHAR1 '\r'
#define TEST_CHAR2 'b'
#define TEST_CHAR3 '\0'
--
2.9.2
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