clang/test/Preprocessor/embed_parameter_limit.c

   1 // RUN: %clang_cc1 -std=c23 %s --embed-dir=%S/Inputs -fsyntax-only -verify
   2
   3 const char data[] = {
   4 #embed <jk.txt>
   5 };
   6 const char offset_data[] = {
   7 #embed <jk.txt> limit(1)
   8 };
   9 static_assert(sizeof(data) == 2);
  10 static_assert('j' == data[0]);
  11 static_assert('k' == data[1]);
  12 static_assert(sizeof(offset_data) == 1);
  13 static_assert('j' == offset_data[0]);
  14 static_assert(offset_data[0] == data[0]);
  15
  16 // Cannot have a negative limit.
  17 #embed <jk.txt> limit(-1)
  18 // expected-error@-1 {{invalid value '-1'; must be positive}}
  19
  20 // It can have a limit of 0, in which case the __has_embed should return false.
  21 #if __has_embed(<jk.txt> limit(0)) != __STDC_EMBED_EMPTY__
  22 #error "__has_embed should return false when there's no data"
  23 #endif
  24
  25 // When the limit is zero, the resource is empty, so if_empty kicks in.
  26 const unsigned char buffer[] = {
  27 #embed <jk.txt> limit(0) if_empty(1)
  28 };
  29 static_assert(sizeof(buffer) == 1);
  30 static_assert(buffer[0] == 1);
  31
  32 // However, prefix and suffix do not kick in.
  33 const unsigned char other_buffer[] = {
  34   1,
  35 #embed <jk.txt> limit(0) prefix(2,) suffix(3)
  36 };
  37 static_assert(sizeof(other_buffer) == 1);
  38 static_assert(other_buffer[0] == 1);
  39
  40 // Ensure we can limit to something larger than the file size as well.
  41 const unsigned char third_buffer[] = {
  42 #embed <jk.txt> limit(100)
  43 };
  44 static_assert(sizeof(third_buffer) == 2);
  45 static_assert('j' == third_buffer[0]);
  46 static_assert('k' == third_buffer[1]);
  47
  48 // Test the limits of a file with more than one character in it.
  49 const unsigned char fourth_buffer[] = {
  50 #embed <media/art.txt> limit(10)
  51 };
  52 static_assert(sizeof(fourth_buffer) == 10);
  53 static_assert(' ' == fourth_buffer[0]);
  54 static_assert(' ' == fourth_buffer[1]);
  55 static_assert(' ' == fourth_buffer[2]);
  56 static_assert(' ' == fourth_buffer[3]);
  57 static_assert(' ' == fourth_buffer[4]);
  58 static_assert(' ' == fourth_buffer[5]);
  59 static_assert(' ' == fourth_buffer[6]);
  60 static_assert(' ' == fourth_buffer[7]);
  61 static_assert(' ' == fourth_buffer[8]);
  62 static_assert(' ' == fourth_buffer[9]);
  63
  64 // Ensure that a limit larger than what can fit into a 64-bit value is
  65 // rejected. This limit is fine because it fits in a 64-bit value.
  66 const unsigned char fifth_buffer[] = {
  67 #embed <jk.txt> limit(0xFFFF'FFFF'FFFF'FFFF)
  68 };
  69 static_assert(sizeof(fifth_buffer) == 2);
  70 static_assert('j' == fifth_buffer[0]);
  71 static_assert('k' == fifth_buffer[1]);
  72
  73 // But this one is not fine because it does not fit into a 64-bit value.
  74 const unsigned char sixth_buffer[] = {
  75 #embed <jk.txt> limit(0xFFFF'FFFF'FFFF'FFFF'1)
  76 };
  77 // expected-error@-2 {{integer literal is too large to be represented in any integer type}}
  78 // Note: the preprocessor will continue with the truncated value, so the parser
  79 // will treat this case and the previous one identically in terms of what
  80 // contents are retained from the embedded resource (which is the entire file).
  81
  82 // Ensure we diagnose duplicate parameters even if they're the same value.
  83 const unsigned char a[] = {
  84 #embed <jk.txt> limit(1) prefix() limit(1)
  85 // expected-error@-1 {{cannot specify parameter 'limit' twice in the same '#embed' directive}}
  86 ,
  87 #embed <jk.txt> limit(1) if_empty() limit(2)
  88 // expected-error@-1 {{cannot specify parameter 'limit' twice in the same '#embed' directive}}
  89 };
  90
  91 // C23 6.10.3.2p2
  92 static_assert(
  93 #embed <jk.txt> limit(defined(FOO)) // expected-error {{'defined' cannot appear within this context}}
  94   == 0); // expected-error {{expected expression}}