[FFmpeg-devel] [PATCH] libavformat/img2dec: fix unable to find svg format when the svg resources start with "<svg"

[FFmpeg-devel] [PATCH] libavformat/img2dec: fix unable to find svg format when the svg resources start with "<svg"

[1035567130]

From: Wang Yaqiang <wangyaqiang03@kuaishou.com>

svg is xml, but <?xml is not required,
 it can start with <svg and can have multiple empty lines.

Signed-off-by: Wang Yaqiang <wangyaqiang03@kuaishou.com>
---
 libavformat/img2dec.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/libavformat/img2dec.c b/libavformat/img2dec.c
index 5a63d7c81d..448a574b59 100644
--- a/libavformat/img2dec.c
+++ b/libavformat/img2dec.c
@@ -25,6 +25,7 @@
 #define _DEFAULT_SOURCE
 #define _BSD_SOURCE
 #include <sys/stat.h>
+#include <ctype.h>
 #include "libavutil/avstring.h"
 #include "libavutil/log.h"
 #include "libavutil/opt.h"
@@ -964,18 +965,19 @@ static int svg_probe(const AVProbeData *p)
 {
     const uint8_t *b = p->buf;
     const uint8_t *end = p->buf + p->buf_size;
-
-    if (memcmp(p->buf, "<?xml", 5))
+    while (b && b < end && isspace(*b)) b++;
+    if (b >= end - 5) return 0;
+    if (memcmp(p->buf, "<?xml", 5) && memcmp(b, "<svg", 4))
         return 0;
     while (b < end) {
         int inc = ff_subtitles_next_line(b);
         if (!inc)
             break;
+        if (!memcmp(b, "<svg", 4))
+            return AVPROBE_SCORE_EXTENSION + 1;
         b += inc;
         if (b >= end - 4)
             return 0;
-        if (!memcmp(b, "<svg", 4))
-            return AVPROBE_SCORE_EXTENSION + 1;
     }
     return 0;
 }
-- 
2.39.2

_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel

To unsubscribe, visit link above, or email
ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".

Re: [FFmpeg-devel] [PATCH] libavformat/img2dec: fix unable to find svg format when the svg resources start with "<svg"

[Marton Balint]

On Tue, 7 Mar 2023, 1035567130@qq.com wrote:

> From: Wang Yaqiang <wangyaqiang03@kuaishou.com>
>
> svg is xml, but <?xml is not required,
> it can start with <svg and can have multiple empty lines.
>
> Signed-off-by: Wang Yaqiang <wangyaqiang03@kuaishou.com>
> ---
> libavformat/img2dec.c | 10 ++++++----
> 1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/libavformat/img2dec.c b/libavformat/img2dec.c
> index 5a63d7c81d..448a574b59 100644
> --- a/libavformat/img2dec.c
> +++ b/libavformat/img2dec.c
> @@ -25,6 +25,7 @@
> #define _DEFAULT_SOURCE
> #define _BSD_SOURCE
> #include <sys/stat.h>
> +#include <ctype.h>

Please no, use libavutil/avstring.h for av_isspace() instead.

> #include "libavutil/avstring.h"
> #include "libavutil/log.h"
> #include "libavutil/opt.h"
> @@ -964,18 +965,19 @@ static int svg_probe(const AVProbeData *p)
> {
>     const uint8_t *b = p->buf;
>     const uint8_t *end = p->buf + p->buf_size;
> -
> -    if (memcmp(p->buf, "<?xml", 5))
> +    while (b && b < end && isspace(*b)) b++;

av_isspace()

> +    if (b >= end - 5) return 0;

line break before return

> +    if (memcmp(p->buf, "<?xml", 5) && memcmp(b, "<svg", 4))
>         return 0;

Why not simply return AVPROBE_SCORE_EXTENSION + 1 here for the <svg case? 
You don't have to change the rest that way which skips the first line 
which supposed to contain <?xml

Regards,
Marton

>     while (b < end) {
>         int inc = ff_subtitles_next_line(b);
>         if (!inc)
>             break;
> +        if (!memcmp(b, "<svg", 4))
> +            return AVPROBE_SCORE_EXTENSION + 1;
>         b += inc;
>         if (b >= end - 4)
>             return 0;
> -        if (!memcmp(b, "<svg", 4))
> -            return AVPROBE_SCORE_EXTENSION + 1;
>     }
>     return 0;
> }
> -- 
> 2.39.2
>
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel@ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
>
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel

To unsubscribe, visit link above, or email
ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".

Re: [FFmpeg-devel] [PATCH] libavformat/img2dec: fix unable to find svg format when the svg resources start with "<svg"

[wangyaqiang]

> 2023年3月9日 07:37，Marton Balint <cus@passwd.hu> 写道：
> 
> 
> On Tue, 7 Mar 2023, 1035567130@qq.com <mailto:1035567130@qq.com> wrote:
> 
>> From: Wang Yaqiang <wangyaqiang03@kuaishou.com>
>> 
>> svg is xml, but <?xml is not required,
>> it can start with <svg and can have multiple empty lines.
>> 
>> Signed-off-by: Wang Yaqiang <wangyaqiang03@kuaishou.com>
>> ---
>> libavformat/img2dec.c | 10 ++++++----
>> 1 file changed, 6 insertions(+), 4 deletions(-)
>> 
>> diff --git a/libavformat/img2dec.c b/libavformat/img2dec.c
>> index 5a63d7c81d..448a574b59 100644
>> --- a/libavformat/img2dec.c
>> +++ b/libavformat/img2dec.c
>> @@ -25,6 +25,7 @@
>> #define _DEFAULT_SOURCE
>> #define _BSD_SOURCE
>> #include <sys/stat.h>
>> +#include <ctype.h>
> 
> Please no, use libavutil/avstring.h for av_isspace() instead.

Thanks，i will fix it

> 
>> #include "libavutil/avstring.h"
>> #include "libavutil/log.h"
>> #include "libavutil/opt.h"
>> @@ -964,18 +965,19 @@ static int svg_probe(const AVProbeData *p)
>> {
>>    const uint8_t *b = p->buf;
>>    const uint8_t *end = p->buf + p->buf_size;
>> -
>> -    if (memcmp(p->buf, "<?xml", 5))
>> +    while (b && b < end && isspace(*b)) b++;
> 
> av_isspace()

Thanks，i will fix it.

> 
>> +    if (b >= end - 5) return 0;
> 
> line break before return

Thanks，i will fix it.

> 
>> +    if (memcmp(p->buf, "<?xml", 5) && memcmp(b, "<svg", 4))
>>        return 0;
> 
> Why not simply return AVPROBE_SCORE_EXTENSION + 1 here for the <svg case? You don't have to change the rest that way which skips the first line which supposed to contain <?xml
> 

Thanks，i will fix it, and fix the case start with "<!—" 

> Regards,
> Marton
> 
>>    while (b < end) {
>>        int inc = ff_subtitles_next_line(b);
>>        if (!inc)
>>            break;
>> +        if (!memcmp(b, "<svg", 4))
>> +            return AVPROBE_SCORE_EXTENSION + 1;
>>        b += inc;
>>        if (b >= end - 4)
>>            return 0;
>> -        if (!memcmp(b, "<svg", 4))
>> -            return AVPROBE_SCORE_EXTENSION + 1;
>>    }
>>    return 0;
>> }
>> -- 
>> 2.39.2
>> 
>> _______________________________________________
>> ffmpeg-devel mailing list
>> ffmpeg-devel@ffmpeg.org <mailto:ffmpeg-devel@ffmpeg.org>
>> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel <https://ffmpeg.org/mailman/listinfo/ffmpeg-devel>
>> 
>> To unsubscribe, visit link above, or email
>> ffmpeg-devel-request@ffmpeg.org <mailto:ffmpeg-devel-request@ffmpeg.org> with subject "unsubscribe".
>> 
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel@ffmpeg.org <mailto:ffmpeg-devel@ffmpeg.org>
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel <https://ffmpeg.org/mailman/listinfo/ffmpeg-devel>
> 
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request@ffmpeg.org <mailto:ffmpeg-devel-request@ffmpeg.org> with subject "unsubscribe".

_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel

To unsubscribe, visit link above, or email
ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".

[FFmpeg-devel] [PATCH v2] libavformat/img2dec: fix unable to find svg format when the svg resources start with "<svg" or "<!---"

[1035567130]

From: Wang Yaqiang <wangyaqiang03@kuaishou.com>

svg is xml, but <?xml is not required,
it can start with <svg and can have multiple empty lines,
or start with <!--- include some comments,
but must first line if start with <?xml.

Signed-off-by: Wang Yaqiang <wangyaqiang03@kuaishou.com>
---
 libavformat/img2dec.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/libavformat/img2dec.c b/libavformat/img2dec.c
index 5a63d7c81d..3488600400 100644
--- a/libavformat/img2dec.c
+++ b/libavformat/img2dec.c
@@ -964,8 +964,13 @@ static int svg_probe(const AVProbeData *p)
 {
     const uint8_t *b = p->buf;
     const uint8_t *end = p->buf + p->buf_size;
-
-    if (memcmp(p->buf, "<?xml", 5))
+    while (b && b < end && av_isspace(*b)) b++;
+    if (b >= end - 5)
+        return 0;
+    if (!memcmp(b, "<svg", 4)) {
+        return AVPROBE_SCORE_EXTENSION + 1;
+    }
+    if (memcmp(p->buf, "<?xml", 5) && memcmp(b, "<!--", 4))
         return 0;
     while (b < end) {
         int inc = ff_subtitles_next_line(b);
-- 
2.39.2

_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel

To unsubscribe, visit link above, or email
ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".

Re: [FFmpeg-devel] [PATCH v2] libavformat/img2dec: fix unable to find svg format when the svg resources start with "<svg" or "<!---"

[Marton Balint]

On Thu, 9 Mar 2023, 1035567130@qq.com wrote:

> From: Wang Yaqiang <wangyaqiang03@kuaishou.com>
>
> svg is xml, but <?xml is not required,
> it can start with <svg and can have multiple empty lines,
> or start with <!--- include some comments,
> but must first line if start with <?xml.

Will apply, thanks.

Marton

>
> Signed-off-by: Wang Yaqiang <wangyaqiang03@kuaishou.com>
> ---
> libavformat/img2dec.c | 9 +++++++--
> 1 file changed, 7 insertions(+), 2 deletions(-)
>
> diff --git a/libavformat/img2dec.c b/libavformat/img2dec.c
> index 5a63d7c81d..3488600400 100644
> --- a/libavformat/img2dec.c
> +++ b/libavformat/img2dec.c
> @@ -964,8 +964,13 @@ static int svg_probe(const AVProbeData *p)
> {
>     const uint8_t *b = p->buf;
>     const uint8_t *end = p->buf + p->buf_size;
> -
> -    if (memcmp(p->buf, "<?xml", 5))
> +    while (b && b < end && av_isspace(*b)) b++;
> +    if (b >= end - 5)
> +        return 0;
> +    if (!memcmp(b, "<svg", 4)) {
> +        return AVPROBE_SCORE_EXTENSION + 1;
> +    }
> +    if (memcmp(p->buf, "<?xml", 5) && memcmp(b, "<!--", 4))
>         return 0;
>     while (b < end) {
>         int inc = ff_subtitles_next_line(b);
> -- 
> 2.39.2
>
> _______________________________________________
> ffmpeg-devel mailing list
> ffmpeg-devel@ffmpeg.org
> https://ffmpeg.org/mailman/listinfo/ffmpeg-devel
>
> To unsubscribe, visit link above, or email
> ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".
>
_______________________________________________
ffmpeg-devel mailing list
ffmpeg-devel@ffmpeg.org
https://ffmpeg.org/mailman/listinfo/ffmpeg-devel

To unsubscribe, visit link above, or email
ffmpeg-devel-request@ffmpeg.org with subject "unsubscribe".