This is useful to write qtest about fw_cfg file entry.

Signed-off-by: Li Qiang <liq3ea@163.com>
---
 tests/libqos/fw_cfg.c | 45 +++++++++++++++++++++++++++++++++++++++++++
 tests/libqos/fw_cfg.h |  2 ++
 2 files changed, 47 insertions(+)

diff --git a/tests/libqos/fw_cfg.c b/tests/libqos/fw_cfg.c
index d0889d1e22..2df33df859 100644
--- a/tests/libqos/fw_cfg.c
+++ b/tests/libqos/fw_cfg.c
@@ -16,12 +16,57 @@
 #include "libqos/fw_cfg.h"
 #include "libqtest.h"
 #include "qemu/bswap.h"
+#include "hw/nvram/fw_cfg.h"
 
 void qfw_cfg_select(QFWCFG *fw_cfg, uint16_t key)
 {
     fw_cfg->select(fw_cfg, key);
 }
 
+/*
+ * The caller need check the return value. When the return value is
+ * nonzero, it means that some bytes have been transferred.
+ *
+ * If the fw_cfg file in question is smaller than the allocated & passed-in
+ * buffer, then the buffer has been populated only in part.
+ *
+ * If the fw_cfg file in question is larger than the passed-in
+ * buffer, then the return value explains how much room would have been
+ * necessary in total. And, while the caller's buffer has been fully
+ * populated, it has received only a starting slice of the fw_cfg file.
+ */
+size_t qfw_cfg_get_file(QFWCFG *fw_cfg, const char *filename,
+                      void *data, size_t buflen)
+{
+    uint32_t count;
+    uint32_t i;
+    unsigned char *filesbuf = NULL;
+    size_t dsize;
+    FWCfgFile *pdir_entry;
+    size_t filesize = 0;
+
+    qfw_cfg_get(fw_cfg, FW_CFG_FILE_DIR, &count, sizeof(count));
+    count = be32_to_cpu(count);
+    dsize = sizeof(uint32_t) + count * sizeof(struct fw_cfg_file);
+    filesbuf = g_malloc0(dsize);
+    qfw_cfg_get(fw_cfg, FW_CFG_FILE_DIR, filesbuf, dsize);
+    pdir_entry = (FWCfgFile *)(filesbuf + sizeof(uint32_t));
+    for (i = 0; i < count; ++i, ++pdir_entry) {
+        if (!strcmp(pdir_entry->name, filename)) {
+            uint32_t len = be32_to_cpu(pdir_entry->size);
+            uint16_t sel = be16_to_cpu(pdir_entry->select);
+            filesize = len;
+            if (len > buflen) {
+                len = buflen;
+            }
+            qfw_cfg_get(fw_cfg, sel, data, len);
+            break;
+        }
+    }
+    g_free(filesbuf);
+    return filesize;
+}
+
 void qfw_cfg_read_data(QFWCFG *fw_cfg, void *data, size_t len)
 {
     fw_cfg->read(fw_cfg, data, len);
diff --git a/tests/libqos/fw_cfg.h b/tests/libqos/fw_cfg.h
index 0353416af0..4996774f7d 100644
--- a/tests/libqos/fw_cfg.h
+++ b/tests/libqos/fw_cfg.h
@@ -31,6 +31,8 @@ void qfw_cfg_get(QFWCFG *fw_cfg, uint16_t key, void *data, size_t len);
 uint16_t qfw_cfg_get_u16(QFWCFG *fw_cfg, uint16_t key);
 uint32_t qfw_cfg_get_u32(QFWCFG *fw_cfg, uint16_t key);
 uint64_t qfw_cfg_get_u64(QFWCFG *fw_cfg, uint16_t key);
+size_t qfw_cfg_get_file(QFWCFG *fw_cfg, const char *filename,
+                        void *data, size_t buflen);
 
 QFWCFG *mm_fw_cfg_init(QTestState *qts, uint64_t base);
 QFWCFG *io_fw_cfg_init(QTestState *qts, uint16_t base);
-- 
2.17.1

On 19/03/2019 03.30, Li Qiang wrote:
> This is useful to write qtest about fw_cfg file entry.
> 
> Signed-off-by: Li Qiang <liq3ea@163.com>
> ---
>  tests/libqos/fw_cfg.c | 45 +++++++++++++++++++++++++++++++++++++++++++
>  tests/libqos/fw_cfg.h |  2 ++
>  2 files changed, 47 insertions(+)
> 
> diff --git a/tests/libqos/fw_cfg.c b/tests/libqos/fw_cfg.c
> index d0889d1e22..2df33df859 100644
> --- a/tests/libqos/fw_cfg.c
> +++ b/tests/libqos/fw_cfg.c
> @@ -16,12 +16,57 @@
>  #include "libqos/fw_cfg.h"
>  #include "libqtest.h"
>  #include "qemu/bswap.h"
> +#include "hw/nvram/fw_cfg.h"
>  
>  void qfw_cfg_select(QFWCFG *fw_cfg, uint16_t key)
>  {
>      fw_cfg->select(fw_cfg, key);
>  }
>  
> +/*
> + * The caller need check the return value. When the return value is
> + * nonzero, it means that some bytes have been transferred.
> + *
> + * If the fw_cfg file in question is smaller than the allocated & passed-in
> + * buffer, then the buffer has been populated only in part.
> + *
> + * If the fw_cfg file in question is larger than the passed-in
> + * buffer, then the return value explains how much room would have been
> + * necessary in total. And, while the caller's buffer has been fully
> + * populated, it has received only a starting slice of the fw_cfg file.
> + */
> +size_t qfw_cfg_get_file(QFWCFG *fw_cfg, const char *filename,
> +                      void *data, size_t buflen)
> +{
> +    uint32_t count;
> +    uint32_t i;
> +    unsigned char *filesbuf = NULL;
> +    size_t dsize;
> +    FWCfgFile *pdir_entry;
> +    size_t filesize = 0;
> +
> +    qfw_cfg_get(fw_cfg, FW_CFG_FILE_DIR, &count, sizeof(count));
> +    count = be32_to_cpu(count);
> +    dsize = sizeof(uint32_t) + count * sizeof(struct fw_cfg_file);
> +    filesbuf = g_malloc0(dsize);
> +    qfw_cfg_get(fw_cfg, FW_CFG_FILE_DIR, filesbuf, dsize);

If I get the code right,  qfw_cfg_get() fills the whole buffer here...
in that case, g_malloc() should be sufficient, so you don't need
g_malloc0() here.

 Thomas

Hi Thomas,

On 4/19/19 9:03 AM, Thomas Huth wrote:
> On 19/03/2019 03.30, Li Qiang wrote:
>> This is useful to write qtest about fw_cfg file entry.
>>
>> Signed-off-by: Li Qiang <liq3ea@163.com>
>> ---
>>  tests/libqos/fw_cfg.c | 45 +++++++++++++++++++++++++++++++++++++++++++
>>  tests/libqos/fw_cfg.h |  2 ++
>>  2 files changed, 47 insertions(+)
>>
>> diff --git a/tests/libqos/fw_cfg.c b/tests/libqos/fw_cfg.c
>> index d0889d1e22..2df33df859 100644
>> --- a/tests/libqos/fw_cfg.c
>> +++ b/tests/libqos/fw_cfg.c
>> @@ -16,12 +16,57 @@
>>  #include "libqos/fw_cfg.h"
>>  #include "libqtest.h"
>>  #include "qemu/bswap.h"
>> +#include "hw/nvram/fw_cfg.h"
>>  
>>  void qfw_cfg_select(QFWCFG *fw_cfg, uint16_t key)
>>  {
>>      fw_cfg->select(fw_cfg, key);
>>  }
>>  
>> +/*
>> + * The caller need check the return value. When the return value is
>> + * nonzero, it means that some bytes have been transferred.
>> + *
>> + * If the fw_cfg file in question is smaller than the allocated & passed-in
>> + * buffer, then the buffer has been populated only in part.
>> + *
>> + * If the fw_cfg file in question is larger than the passed-in
>> + * buffer, then the return value explains how much room would have been
>> + * necessary in total. And, while the caller's buffer has been fully
>> + * populated, it has received only a starting slice of the fw_cfg file.
>> + */
>> +size_t qfw_cfg_get_file(QFWCFG *fw_cfg, const char *filename,
>> +                      void *data, size_t buflen)
>> +{
>> +    uint32_t count;
>> +    uint32_t i;
>> +    unsigned char *filesbuf = NULL;
>> +    size_t dsize;
>> +    FWCfgFile *pdir_entry;
>> +    size_t filesize = 0;
>> +
>> +    qfw_cfg_get(fw_cfg, FW_CFG_FILE_DIR, &count, sizeof(count));
>> +    count = be32_to_cpu(count);
>> +    dsize = sizeof(uint32_t) + count * sizeof(struct fw_cfg_file);
>> +    filesbuf = g_malloc0(dsize);
>> +    qfw_cfg_get(fw_cfg, FW_CFG_FILE_DIR, filesbuf, dsize);
> 
> If I get the code right,  qfw_cfg_get() fills the whole buffer here...
> in that case, g_malloc() should be sufficient, so you don't need
> g_malloc0() here.

Correct.

Apparently Li did address your suggestion in his next iteration of this
patch (same subject, Message-Id: <20190420100056.116305-3-liq3ea@163.com>).

Thanks,

Phil.