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capsel wrote: |
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|
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>Hi all, |
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> |
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>is it a bug in glibc or in my code? |
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> |
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> |
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|
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This is so far off topic, it isn't even funny. But, I see a couple bugs |
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in your code. I will cover them inline: |
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|
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> if( ( config_content == NULL ) || ( config_content==0 ) ) |
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> |
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> |
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|
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Not really a bug here, but since NULL and 0 are the same value, you only |
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need one side of the comparison. |
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|
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> *(lines) = config_content; |
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> for( i = 0; i < config_contentl; i++ ) |
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> { |
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> if( *(config_content+i) == '\n' ) |
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> { |
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> lines = (char**) realloc( lines, sizeof( char** )*(linesc+1) ); |
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> if( lines == NULL ) |
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> { |
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> fprintf( logi, "=> B³±d alokacji\n" ); |
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> return 0; |
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> } |
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> linesc++; |
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> *(lines+linesc) = (config_content+i+1); |
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> *(config_content+i) = '\0'; |
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> printf( "-> linesc++\n" ); |
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> } |
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> } |
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> |
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> |
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|
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There is a possible off-by-one error for linesc if config_content does |
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not end with a newline. For example, consider a config file with a |
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single line that does not end with a newline. In that case, linesc will |
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be 0 in your code, and you will not process anything. |
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|
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I suggest setting linesc = 1 before the loop, and then adjust the |
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internals appropriately. |
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|
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> fprintf( stdout, "-> linesc = %u\n", linesc ); |
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> for( i = 0; i < linesc; i++ ) |
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> { |
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> if( *(*(lines+i)) == '#' ) |
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> { |
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> continue; |
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> } |
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> |
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> |
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|
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Again, not a bug, but a readability recommendation. Use a temporary |
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variable inside your loop for the current line: |
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|
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char* line = lines[i]; |
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|
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Then replace all "*(lines+i)" with "line". |
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|
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> if( strcmp( "log", *(lines+i) ) == 0 ) |
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> { |
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> config_configpathl = strlen( eqch+1 ); |
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> config_configpath = (char*) malloc( config_configpathl ); |
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> if( config_configpath == NULL ) |
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> { |
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> fprintf( logi, "=> B³±d alokacji pamiêci na nazwe pliku loga dla linii %i\n",i ); |
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> free( lines ); |
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> return 0; |
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> } |
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> strcpy( config_configpath, eqch+1 ); |
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> fprintf( stdout, "-> log = `%s'\n", eqch+1 ); |
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> continue; |
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> } |
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> |
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> |
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|
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This is your major bug, a memory overflow. You are only allocated |
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enough memory for the characters of the string, not including the |
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terminating null character. Strcpy copies the characters of the string, |
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_plus_ the terminating null, which is where you get a memory overflow. |
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|
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Get rid of config_configpathl and the strlen line, and replace the |
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malloc and strcpy with strdup(). |
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|
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-Richard |
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|
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-- |
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