Hello, I've been working hard with my implementation and I almost got it. I'd say it's working fine in Safari but I got a DOM exception in Chrome and Firefox and I have no idea why. the DOM Exception doesn't give any message nor error code... The error happens when inside my C code i have an EM_ASM_ARGS() block and inside this I use the Javascript WebCrypto API to decrypt the image. The think is the same decrypt method works when I use it outside emscripten in a normal webpage and inside emscripten it works with Safari! But why it doesn't work in Chrome?
Thanks 2015-10-20 21:24 GMT-07:00 Alon Zakai <[email protected]>: > Yes, malloc the space, and memcpy the contents to that space. > > On Tue, Oct 20, 2015 at 8:20 PM, Pau Ballart <[email protected]> wrote: > >> I did some tries with no success. >> If I have this declaration: >> *int p3stuff(char *imgUrl, unsigned char *wrappedkey);* >> How can I make sure the contents of imgUrl will persist even out of the >> scope? >> Because it's a pointer so maybe I need to malloc first the space and then >> memcpy the contents? >> Suppose I have a global var like this *char *imageUrl;* I'd be very >> thankful if you can provide me an example. >> >> 2015-10-20 15:57 GMT-07:00 Alon Zakai <[email protected]>: >> >>> Yes, if you want something to live beyond the current function call, you >>> should use malloc(). That will only be reused after you call free() on it. >>> >>> On Tue, Oct 20, 2015 at 3:51 PM, Pau Ballart <[email protected]> wrote: >>> >>>> Updated to 1.35 but same problem... >>>> Maybe the question to formulate would be: How can I save in a >>>> global/static variable some information so that I can acces it later in the >>>> callback function and make sure it's not overwritten? >>>> What do you think about using malloc() somehow? Would it work? >>>> >>>> 2015-10-20 14:18 GMT-07:00 Alon Zakai <[email protected]>: >>>> >>>>> Might be worth trying current master (or incoming) then, which is now >>>>> 1.35.0. >>>>> >>>>> On Tue, Oct 20, 2015 at 2:16 PM, Pau Ballart <[email protected]> >>>>> wrote: >>>>> >>>>>> $ emcc -v >>>>>> emcc (Emscripten gcc/clang-like replacement + linker emulating GNU >>>>>> ld) 1.34.8 >>>>>> clang version 3.7.0 >>>>>> Target: x86_64-apple-darwin15.0.0 >>>>>> Thread model: posix >>>>>> INFO root: (Emscripten: Running sanity checks) >>>>>> >>>>>> 2015-10-20 14:05 GMT-07:00 Alon Zakai <[email protected]>: >>>>>> >>>>>>> One possible issue is that if those values are on the stack, and the >>>>>>> scope exits, then that stack memory might be reused. For example this is >>>>>>> unsafe: >>>>>>> >>>>>>> { >>>>>>> char buffer[100]; >>>>>>> // write into buffer >>>>>>> emscripten_async_wget(..., (void*)buffer); >>>>>>> } >>>>>>> >>>>>>> The buffer will be released before the async callback occurs, and >>>>>>> other data might be written into it before the callback reads from it. >>>>>>> >>>>>>> Which version of emscripten are you using, btw? I remember a while >>>>>>> back we had a bug around this. >>>>>>> >>>>>>> On Tue, Oct 20, 2015 at 1:36 PM, Pau Ballart <[email protected]> >>>>>>> wrote: >>>>>>> >>>>>>>> Hello, >>>>>>>> >>>>>>>> After some research and some refactor I did the following: >>>>>>>> >>>>>>>> - In my p3stuff function I >>>>>>>> call emscripten_set_main_loop(wait_wgets, 0, 0); so the application >>>>>>>> is not >>>>>>>> terminated. >>>>>>>> - In wait_wgets I call the emscripten_async_wget(imageUrl, >>>>>>>> path, onLoaded, onError); only the first time the method is called. >>>>>>>> - In the onLoaded callback I >>>>>>>> call emscripten_cancel_main_loop(); and then I call my c code that >>>>>>>> perform >>>>>>>> the jpeg stuff. >>>>>>>> >>>>>>>> Problem is: >>>>>>>> the p3stuff function has 2 arguments: int p3stuff(char *imgUrl, >>>>>>>> unsigned char *wrappedkey) >>>>>>>> When it's called i have two global variables unsigned char >>>>>>>> *wrappedKey; and char *imageUrl; which are assigned with the argument >>>>>>>> like >>>>>>>> that: >>>>>>>> >>>>>>>> wrappedKey = wrappedkey; >>>>>>>> imageUrl = imgUrl; >>>>>>>> >>>>>>>> I do that in order to access the image url from the wait_wgets() or >>>>>>>> the wrapped key from the onLoaded callback but I think there is some >>>>>>>> memory >>>>>>>> management problems cause if I print the url just before calling >>>>>>>> emscripten_async_wget the imageUrl variable content is completely >>>>>>>> rubbish >>>>>>>> but id I don't print anything it works. >>>>>>>> >>>>>>>> So how can I use the global variables in C in order to not get >>>>>>>> overwritten? Maybe using malloc, or memcopy? >>>>>>>> >>>>>>>> Thanks, >>>>>>>> >>>>>>>> Pau >>>>>>>> >>>>>>>> 2015-10-19 10:53 GMT-07:00 Pau Ballart <[email protected]>: >>>>>>>> >>>>>>>>> Okay I will try the async version and let you know. >>>>>>>>> >>>>>>>>> Thanks >>>>>>>>> >>>>>>>>> 2015-10-17 19:37 GMT-07:00 Alon Zakai <[email protected]>: >>>>>>>>> >>>>>>>>>> The only tricky thing with emscripten_wget is that as mentioned >>>>>>>>>> in the docs, >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> http://kripken.github.io/emscripten-site/docs/api_reference/emscripten.h.html#c.emscripten_wget >>>>>>>>>> >>>>>>>>>> it requires the ASYNCIFY option. It's easier in general to use >>>>>>>>>> the async version, emscripten_async_wget, which does not require >>>>>>>>>> ASYNCIFY. >>>>>>>>>> >>>>>>>>>> >>>>>>>>>> On Sat, Oct 17, 2015 at 10:47 AM, Pau Ballart <[email protected] >>>>>>>>>> > wrote: >>>>>>>>>> >>>>>>>>>>> I think the php code is correct so I'm just trying to download >>>>>>>>>>> an image and process it's data but I think I'm missing something >>>>>>>>>>> about the >>>>>>>>>>> lifecycle or wget function because I get unexpected exit errors. >>>>>>>>>>> >>>>>>>>>>> So I'd like to know if the emscripten_wget(imgUrl, path); is >>>>>>>>>>> correct because I have the weirdest behaviour ever that depending >>>>>>>>>>> on the >>>>>>>>>>> p3stuff function param "wrappedkey" the download succeeds or >>>>>>>>>>> not. >>>>>>>>>>> >>>>>>>>>>> 2015-10-15 17:07 GMT-07:00 Alon Zakai <[email protected]>: >>>>>>>>>>> >>>>>>>>>>>> I see you have >>>>>>>>>>>> >>>>>>>>>>>> P3Func = Module.cwrap('p3stuff', 'number', ['string', >>>>>>>>>>>> 'string']); >>>>>>>>>>>> >>>>>>>>>>>> which looks good. You can then call it with something like >>>>>>>>>>>> >>>>>>>>>>>> result = P3Func('first', 'second'); >>>>>>>>>>>> >>>>>>>>>>>> which I see you are doing. What part of that are you trying to >>>>>>>>>>>> improve? >>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> On Thu, Oct 15, 2015 at 12:59 PM, Pau Ballart < >>>>>>>>>>>> [email protected]> wrote: >>>>>>>>>>>> >>>>>>>>>>>>> Okay so the php is just calling a function I declared. Because >>>>>>>>>>>>> I need to pass the image url as an argument and a key, I don't >>>>>>>>>>>>> know how to >>>>>>>>>>>>> do it using the main function so I changed the main function for >>>>>>>>>>>>> this one >>>>>>>>>>>>> with the two arguments and then called this function from my php >>>>>>>>>>>>> code. >>>>>>>>>>>>> Is there a better way to call emscripten passing parameters? >>>>>>>>>>>>> >>>>>>>>>>>>> Thanks. >>>>>>>>>>>>> >>>>>>>>>>>>> 2015-10-15 12:55 GMT-07:00 Alon Zakai <[email protected]>: >>>>>>>>>>>>> >>>>>>>>>>>>>> It would be good to focus the question more, it's hard to >>>>>>>>>>>>>> tell what the core issue is. Try to reduce the problem to just >>>>>>>>>>>>>> one concrete >>>>>>>>>>>>>> thing, like just loading a file, and doing it without that >>>>>>>>>>>>>> custom PHP >>>>>>>>>>>>>> script, for example. >>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> On Thu, Oct 15, 2015 at 12:27 PM, Pau Ballart < >>>>>>>>>>>>>> [email protected]> wrote: >>>>>>>>>>>>>> >>>>>>>>>>>>>>> Hello developers, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> I'm starting a project and I'm new at Javascript and >>>>>>>>>>>>>>> emscripten. I'm trying to download some image data from a >>>>>>>>>>>>>>> server and then >>>>>>>>>>>>>>> process it using some c functions I already have working. I >>>>>>>>>>>>>>> asked this >>>>>>>>>>>>>>> question in Stackoverflow so I share you the link and maybe one >>>>>>>>>>>>>>> of you can >>>>>>>>>>>>>>> help me. >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> http://stackoverflow.com/questions/33087205/emscripten-code-for-image-data-download-using-emscripten-wget-or-emscripten-asyn >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Thank you, >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> Pau B >>>>>>>>>>>>>>> >>>>>>>>>>>>>>> -- >>>>>>>>>>>>>>> You received this message because you are subscribed to the >>>>>>>>>>>>>>> Google Groups "emscripten-discuss" group. >>>>>>>>>>>>>>> To unsubscribe from this group and stop receiving emails >>>>>>>>>>>>>>> from it, send an email to >>>>>>>>>>>>>>> [email protected]. >>>>>>>>>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>>>>>>>>> >>>>>>>>>>>>>> >>>>>>>>>>>>>> -- >>>>>>>>>>>>>> You received this message because you are subscribed to a >>>>>>>>>>>>>> topic in the Google Groups "emscripten-discuss" group. >>>>>>>>>>>>>> To unsubscribe from this topic, visit >>>>>>>>>>>>>> https://groups.google.com/d/topic/emscripten-discuss/BEb-1mjDvZI/unsubscribe >>>>>>>>>>>>>> . >>>>>>>>>>>>>> To unsubscribe from this group and all its topics, send an >>>>>>>>>>>>>> email to [email protected]. >>>>>>>>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> >>>>>>>>>>>>> -- >>>>>>>>>>>>> Pau Ballart >>>>>>>>>>>>> >>>>>>>>>>>>> -- >>>>>>>>>>>>> You received this message because you are subscribed to the >>>>>>>>>>>>> Google Groups "emscripten-discuss" group. >>>>>>>>>>>>> To unsubscribe from this group and stop receiving emails from >>>>>>>>>>>>> it, send an email to >>>>>>>>>>>>> [email protected]. >>>>>>>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>>>>>>> >>>>>>>>>>>> >>>>>>>>>>>> -- >>>>>>>>>>>> You received this message because you are subscribed to a topic >>>>>>>>>>>> in the Google Groups "emscripten-discuss" group. >>>>>>>>>>>> To unsubscribe from this topic, visit >>>>>>>>>>>> https://groups.google.com/d/topic/emscripten-discuss/BEb-1mjDvZI/unsubscribe >>>>>>>>>>>> . >>>>>>>>>>>> To unsubscribe from this group and all its topics, send an >>>>>>>>>>>> email to [email protected]. >>>>>>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> >>>>>>>>>>> -- >>>>>>>>>>> Pau Ballart >>>>>>>>>>> >>>>>>>>>>> -- >>>>>>>>>>> You received this message because you are subscribed to the >>>>>>>>>>> Google Groups "emscripten-discuss" group. >>>>>>>>>>> To unsubscribe from this group and stop receiving emails from >>>>>>>>>>> it, send an email to >>>>>>>>>>> [email protected]. >>>>>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>>>>> >>>>>>>>>> >>>>>>>>>> -- >>>>>>>>>> You received this message because you are subscribed to a topic >>>>>>>>>> in the Google Groups "emscripten-discuss" group. >>>>>>>>>> To unsubscribe from this topic, visit >>>>>>>>>> https://groups.google.com/d/topic/emscripten-discuss/BEb-1mjDvZI/unsubscribe >>>>>>>>>> . >>>>>>>>>> To unsubscribe from this group and all its topics, send an email >>>>>>>>>> to [email protected]. >>>>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> >>>>>>>>> -- >>>>>>>>> Pau Ballart >>>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> >>>>>>>> -- >>>>>>>> Pau Ballart >>>>>>>> >>>>>>>> -- >>>>>>>> You received this message because you are subscribed to the Google >>>>>>>> Groups "emscripten-discuss" group. >>>>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>>>> send an email to [email protected]. >>>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>>> >>>>>>> >>>>>>> -- >>>>>>> You received this message because you are subscribed to a topic in >>>>>>> the Google Groups "emscripten-discuss" group. >>>>>>> To unsubscribe from this topic, visit >>>>>>> https://groups.google.com/d/topic/emscripten-discuss/BEb-1mjDvZI/unsubscribe >>>>>>> . >>>>>>> To unsubscribe from this group and all its topics, send an email to >>>>>>> [email protected]. >>>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>>> >>>>>> >>>>>> >>>>>> >>>>>> -- >>>>>> Pau Ballart >>>>>> >>>>>> -- >>>>>> You received this message because you are subscribed to the Google >>>>>> Groups "emscripten-discuss" group. >>>>>> To unsubscribe from this group and stop receiving emails from it, >>>>>> send an email to [email protected]. >>>>>> For more options, visit https://groups.google.com/d/optout. >>>>>> >>>>> >>>>> -- >>>>> You received this message because you are subscribed to a topic in the >>>>> Google Groups "emscripten-discuss" group. >>>>> To unsubscribe from this topic, visit >>>>> https://groups.google.com/d/topic/emscripten-discuss/BEb-1mjDvZI/unsubscribe >>>>> . >>>>> To unsubscribe from this group and all its topics, send an email to >>>>> [email protected]. >>>>> For more options, visit https://groups.google.com/d/optout. >>>>> >>>> >>>> >>>> >>>> -- >>>> Pau Ballart >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "emscripten-discuss" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> >>> -- >>> You received this message because you are subscribed to a topic in the >>> Google Groups "emscripten-discuss" group. >>> To unsubscribe from this topic, visit >>> https://groups.google.com/d/topic/emscripten-discuss/BEb-1mjDvZI/unsubscribe >>> . >>> To unsubscribe from this group and all its topics, send an email to >>> [email protected]. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> >> >> -- >> Pau Ballart >> >> -- >> You received this message because you are subscribed to the Google Groups >> "emscripten-discuss" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected]. >> For more options, visit https://groups.google.com/d/optout. >> > > -- > You received this message because you are subscribed to a topic in the > Google Groups "emscripten-discuss" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/emscripten-discuss/BEb-1mjDvZI/unsubscribe > . > To unsubscribe from this group and all its topics, send an email to > [email protected]. > For more options, visit https://groups.google.com/d/optout. > -- Pau Ballart -- You received this message because you are subscribed to the Google Groups "emscripten-discuss" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
