1 /* Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
2    file Copyright.txt or https://cmake.org/licensing for details.  */
3 #include "cmCMakeMinimumRequired.h"
4 
5 #include <cstdio>
6 #include <sstream>
7 
8 #include "cmExecutionStatus.h"
9 #include "cmMakefile.h"
10 #include "cmMessageType.h"
11 #include "cmSystemTools.h"
12 #include "cmVersion.h"
13 
14 namespace {
15 bool EnforceUnknownArguments(std::string const& version_max,
16                              std::vector<std::string> const& unknown_arguments,
17                              cmExecutionStatus& status);
18 }
19 
20 // cmCMakeMinimumRequired
cmCMakeMinimumRequired(std::vector<std::string> const & args,cmExecutionStatus & status)21 bool cmCMakeMinimumRequired(std::vector<std::string> const& args,
22                             cmExecutionStatus& status)
23 {
24   // Process arguments.
25   std::string version_string;
26   bool doing_version = false;
27   std::vector<std::string> unknown_arguments;
28   for (std::string const& arg : args) {
29     if (arg == "VERSION") {
30       doing_version = true;
31     } else if (arg == "FATAL_ERROR") {
32       if (doing_version) {
33         status.SetError("called with no value for VERSION.");
34         return false;
35       }
36       doing_version = false;
37     } else if (doing_version) {
38       doing_version = false;
39       version_string = arg;
40     } else {
41       unknown_arguments.push_back(arg);
42     }
43   }
44   if (doing_version) {
45     status.SetError("called with no value for VERSION.");
46     return false;
47   }
48 
49   // Make sure there was a version to check.
50   if (version_string.empty()) {
51     return EnforceUnknownArguments(std::string(), unknown_arguments, status);
52   }
53 
54   // Separate the <min> version and any trailing ...<max> component.
55   std::string::size_type const dd = version_string.find("...");
56   std::string const version_min = version_string.substr(0, dd);
57   std::string const version_max = dd != std::string::npos
58     ? version_string.substr(dd + 3, std::string::npos)
59     : std::string();
60   if (dd != std::string::npos &&
61       (version_min.empty() || version_max.empty())) {
62     std::ostringstream e;
63     e << "VERSION \"" << version_string
64       << R"(" does not have a version on both sides of "...".)";
65     status.SetError(e.str());
66     return false;
67   }
68 
69   // Save the required version string.
70   status.GetMakefile().AddDefinition("CMAKE_MINIMUM_REQUIRED_VERSION",
71                                      version_min);
72 
73   // Get the current version number.
74   unsigned int current_major = cmVersion::GetMajorVersion();
75   unsigned int current_minor = cmVersion::GetMinorVersion();
76   unsigned int current_patch = cmVersion::GetPatchVersion();
77   unsigned int current_tweak = cmVersion::GetTweakVersion();
78 
79   // Parse at least two components of the version number.
80   // Use zero for those not specified.
81   unsigned int required_major = 0;
82   unsigned int required_minor = 0;
83   unsigned int required_patch = 0;
84   unsigned int required_tweak = 0;
85   if (sscanf(version_min.c_str(), "%u.%u.%u.%u", &required_major,
86              &required_minor, &required_patch, &required_tweak) < 2) {
87     std::ostringstream e;
88     e << "could not parse VERSION \"" << version_min << "\".";
89     status.SetError(e.str());
90     return false;
91   }
92 
93   // Compare the version numbers.
94   if ((current_major < required_major) ||
95       (current_major == required_major && current_minor < required_minor) ||
96       (current_major == required_major && current_minor == required_minor &&
97        current_patch < required_patch) ||
98       (current_major == required_major && current_minor == required_minor &&
99        current_patch == required_patch && current_tweak < required_tweak)) {
100     // The current version is too low.
101     std::ostringstream e;
102     e << "CMake " << version_min
103       << " or higher is required.  You are running version "
104       << cmVersion::GetCMakeVersion();
105     status.GetMakefile().IssueMessage(MessageType::FATAL_ERROR, e.str());
106     cmSystemTools::SetFatalErrorOccured();
107     return true;
108   }
109 
110   // The version is not from the future, so enforce unknown arguments.
111   if (!EnforceUnknownArguments(version_max, unknown_arguments, status)) {
112     return false;
113   }
114 
115   if (required_major < 2 || (required_major == 2 && required_minor < 4)) {
116     status.GetMakefile().IssueMessage(
117       MessageType::AUTHOR_WARNING,
118       "Compatibility with CMake < 2.4 is not supported by CMake >= 3.0.");
119     status.GetMakefile().SetPolicyVersion("2.4", version_max);
120   } else {
121     status.GetMakefile().SetPolicyVersion(version_min, version_max);
122   }
123 
124   return true;
125 }
126 
127 namespace {
EnforceUnknownArguments(std::string const & version_max,std::vector<std::string> const & unknown_arguments,cmExecutionStatus & status)128 bool EnforceUnknownArguments(std::string const& version_max,
129                              std::vector<std::string> const& unknown_arguments,
130                              cmExecutionStatus& status)
131 {
132   if (unknown_arguments.empty()) {
133     return true;
134   }
135 
136   // Consider the max version if at least two components were given.
137   unsigned int max_major = 0;
138   unsigned int max_minor = 0;
139   unsigned int max_patch = 0;
140   unsigned int max_tweak = 0;
141   if (sscanf(version_max.c_str(), "%u.%u.%u.%u", &max_major, &max_minor,
142              &max_patch, &max_tweak) >= 2) {
143     unsigned int current_major = cmVersion::GetMajorVersion();
144     unsigned int current_minor = cmVersion::GetMinorVersion();
145     unsigned int current_patch = cmVersion::GetPatchVersion();
146     unsigned int current_tweak = cmVersion::GetTweakVersion();
147 
148     if ((current_major < max_major) ||
149         (current_major == max_major && current_minor < max_minor) ||
150         (current_major == max_major && current_minor == max_minor &&
151          current_patch < max_patch) ||
152         (current_major == max_major && current_minor == max_minor &&
153          current_patch == max_patch && current_tweak < max_tweak)) {
154       // A ...<max> version was given that is larger than the current
155       // version of CMake, so tolerate unknown arguments.
156       return true;
157     }
158   }
159 
160   std::ostringstream e;
161   e << "called with unknown argument \"" << unknown_arguments[0] << "\".";
162   status.SetError(e.str());
163   return false;
164 }
165 }
166